An original Thinka practice paper modelled on the structure and difficulty of the Jun 2025 (V2) Cambridge International A Level Mathematics (0580) paper. Not affiliated with or reproduced from Cambridge.
Extended Written Section
Answer all questions. Calculators should be used where appropriate. Give non-exact numerical answers correct to 3 significant figures, or 1 decimal place for angles in degrees, unless specified otherwise.
Factorise the quadratic expression: \(2x^2 + 5x - 12 = (2x - 3)(x + 4) = 0\). Set each factor to zero: \(2x - 3 = 0 \implies x = 1.5\) and \(x + 4 = 0 \implies x = -4\).
PastPaper.markingScheme
M1 for correct factorisation \((2x - 3)(x + 4)\) or correct use of the quadratic formula. A1 for both solutions: \(1.5\) (or \(\frac{3}{2}\)) and \(-4\).
PastPaper.question 3 · Short Answer
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In triangle \(ABC\), \(AB = 7\text{ cm}\), \(BC = 9\text{ cm}\) and angle \(ABC = 42^\circ\). Calculate the area of the triangle.
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PastPaper.workedSolution
Use the area formula for a non-right-angled triangle: \(\text{Area} = \frac{1}{2} a b \sin C\). Here, \(\text{Area} = \frac{1}{2} \times 7 \times 9 \times \sin(42^\circ) = 31.5 \times 0.66913... = 21.0776...\text{ cm}^2\). Rounding to 3 significant figures gives \(21.1\text{ cm}^2\).
PastPaper.markingScheme
M1 for \(\frac{1}{2} \times 7 \times 9 \times \sin(42)\). A1 for \(21.1\) (accept answers in the range \([21.07, 21.1]\)).
PastPaper.question 4 · Short Answer
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In triangle \(PQR\), \(PQ = 8\text{ cm}\), \(QR = 11\text{ cm}\) and angle \(PQR = 105^\circ\). Calculate the length of \(PR\).
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PastPaper.workedSolution
Use the cosine rule: \(PR^2 = PQ^2 + QR^2 - 2 \times PQ \times QR \times \cos(PQR)\). Substitute the given values: \(PR^2 = 8^2 + 11^2 - 2 \times 8 \times 11 \times \cos(105^\circ) = 64 + 121 - 176 \times (-0.258819...) = 185 + 45.552... = 230.552...\). Take the square root: \(PR = \sqrt{230.552...} = 15.1839...\text{ cm}\). Rounding to 3 significant figures gives \(15.2\text{ cm}\).
PastPaper.markingScheme
M1 for a correct substitution into the Cosine Rule: \(8^2 + 11^2 - 2 \times 8 \times 11 \times \cos(105)\). A1 for \(15.2\) (accept answers in the range \([15.15, 15.25]\)).
PastPaper.question 5 · Short Answer
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A bag contains 5 red balls and 3 blue balls. Two balls are selected at random, one after the other, without replacement. Find the probability that both balls are red.
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PastPaper.workedSolution
The probability that the first ball is red is \(\frac{5}{8}\). Since the selection is without replacement, there are now 4 red balls left out of a total of 7 balls. The probability that the second ball is red given that the first was red is \(\frac{4}{7}\). The probability that both balls are red is \(\frac{5}{8} \times \frac{4}{7} = \frac{20}{56} = \frac{5}{14}\).
PastPaper.markingScheme
M1 for \(\frac{5}{8} \times \frac{4}{7}\). A1 for \(\frac{5}{14}\) or equivalent fraction, or \(0.357\) (accept \([0.357, 0.358]\)).
PastPaper.question 6 · Short Answer
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In a class of 30 students, 18 study Physics, 15 study Chemistry and 8 study both subjects. A student is chosen at random. Given that this student studies Physics, find the probability that they also study Chemistry.
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PastPaper.workedSolution
We are looking for the conditional probability \(P(\text{Chemistry} | \text{Physics})\). The number of students who study Physics is 18. Of these 18 students, 8 also study Chemistry. Therefore, the probability is \(\frac{8}{18} = \frac{4}{9}\).
PastPaper.markingScheme
M1 for a fraction with 18 in the denominator, or \(\frac{8/30}{18/30}\). A1 for \(\frac{4}{9}\) or equivalent fraction, or \(0.444\) (accept \([0.444, 0.445]\)).
PastPaper.question 7 · Short Answer
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Find the equation of the line perpendicular to \(y = 3x - 5\) that passes through the point \((6, 2)\). Give your answer in the form \(y = mx + c\).
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PastPaper.workedSolution
The gradient of the line \(y = 3x - 5\) is 3. The gradient of the perpendicular line is the negative reciprocal: \(m = -\frac{1}{3}\). Using the point-slope form \(y - y_1 = m(x - x_1)\) with the point \((6, 2)\): \(y - 2 = -\frac{1}{3}(x - 6)\). Simplifying gives: \(y - 2 = -\frac{1}{3}x + 2 \implies y = -\frac{1}{3}x + 4\).
PastPaper.markingScheme
M1 for gradient of perpendicular line \(= -\frac{1}{3}\). A1 for \(y = -\frac{1}{3}x + 4\) or any equivalent fully simplified form (e.g., \(y = -0.333x + 4\)).
PastPaper.question 8 · Short Answer
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The line \(L\) is perpendicular to the line with equation \(2x + 5y = 10\). Find the gradient of line \(L\).
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PastPaper.workedSolution
First, find the gradient of the given line by rearranging it into \(y = mx + c\) form: \(5y = -2x + 10 \implies y = -\frac{2}{5}x + 2\). The gradient of this line is \(-\frac{2}{5}\) (or \(-0.4\)). Since line \(L\) is perpendicular, its gradient is the negative reciprocal: \(m = -\frac{1}{-2/5} = \frac{5}{2} = 2.5\).
PastPaper.markingScheme
M1 for finding the gradient of the given line, e.g., \(-\frac{2}{5}\) or \(-0.4\). A1 for \(2.5\) or \(\frac{5}{2}\).
PastPaper.question 9 · Short Answer
2 PastPaper.marks
Solve the equation.
$$\frac{x+2}{3} - \frac{x-1}{4} = 2$$
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PastPaper.workedSolution
To solve the equation, first multiply all terms by $12$ (the lowest common multiple of the denominators) to clear the fractions:
$$4(x + 2) - 3(x - 1) = 24$$
Expand the brackets:
$$4x + 8 - 3x + 3 = 24$$
Simplify the left-hand side by combining like terms:
$$x + 11 = 24$$
Subtract $11$ from both sides of the equation:
$$x = 13$$
PastPaper.markingScheme
M1 for correctly clearing fractions to obtain a linear equation, e.g., $4(x+2) - 3(x-1) = 24$ (or equivalent) A1 for $13$ (or $x = 13$)
PastPaper.question 10 · Short Answer
2 PastPaper.marks
In triangle $ABC$, $AB = 8\text{ cm}$, $AC = 11\text{ cm}$, and angle $ACB = 34^\circ$. Calculate the acute angle $ABC$.
M1 for correct substitution into the sine rule, e.g., $\frac{\sin(\angle ABC)}{11} = \frac{\sin(34^\circ)}{8}$ A1 for $50.3$ (or $50.25$ to $50.3$)
PastPaper.question 11 · Short Answer
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The probability that a student at a college plays tennis is $0.4$. The probability that a student plays both tennis and squash is $0.12$. Find the probability that a student plays squash, given that they play tennis.
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PastPaper.workedSolution
Use the formula for conditional probability:
$$P(\text{Squash} | \text{Tennis}) = \frac{P(\text{Tennis and Squash})}{P(\text{Tennis})}$$
M1 for writing $\frac{0.12}{0.4}$ or for a correct conditional probability expression A1 for $0.3$ (or equivalent fraction, e.g., $\frac{3}{10}$)
PastPaper.question 12 · Short Answer
2 PastPaper.marks
Find the equation of the line perpendicular to $y = 3x - 5$ that passes through the point $(6, 2)$. Give your answer in the form $y = mx + c$.
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PastPaper.workedSolution
The gradient of the line $y = 3x - 5$ is $3$. Since the lines are perpendicular, the gradient, $m$, of the perpendicular line is the negative reciprocal:
$$m = -\frac{1}{3}$$
Use the equation of a straight line, $y - y_1 = m(x - x_1)$, with the point $(6, 2)$:
$$y - 2 = -\frac{1}{3}(x - 6)$$
$$y - 2 = -\frac{1}{3}x + 2$$
$$y = -\frac{1}{3}x + 4$$
PastPaper.markingScheme
M1 for identifying the perpendicular gradient as $-\frac{1}{3}$ (or $-0.333$) A1 for $y = -\frac{1}{3}x + 4$ or equivalent (e.g., $y = -0.333x + 4$)
To eliminate $y$, multiply the second equation by $2$:
$$10x - 2y = 22$$
Now, add this new equation to the first equation:
$$(3x + 2y) + (10x - 2y) = 17 + 22$$
$$13x = 39$$
$$x = 3$$
Substitute $x = 3$ back into the second equation to find $y$:
$$5(3) - y = 11$$
$$15 - y = 11$$
$$y = 4$$
Thus, $x = 3$ and $y = 4$.
PastPaper.markingScheme
M1 for a correct attempt to eliminate one variable (e.g., multiplying the second equation by 2 and adding, or writing $y = 5x - 11$ and substituting) A1 for $x = 3, y = 4$ (both correct)
PastPaper.question 14 · Short Answer
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A triangle $PQR$ has sides $PQ = 9\text{ cm}$ and $QR = 14\text{ cm}$. The area of the triangle is $45\text{ cm}^2$. Calculate the acute angle $PQR$.
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PastPaper.workedSolution
Use the formula for the area of a non-right-angled triangle:
M1 for setting up the area equation, e.g., $45 = \frac{1}{2} \times 9 \times 14 \times \sin(\angle PQR)$ or $\sin(\angle PQR) = \frac{5}{7}$ A1 for $45.6$ (or $45.58\dots$)
PastPaper.question 15 · Short Answer
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Find the equation of the perpendicular bisector of the line segment joining $A(2, 5)$ and $B(8, 1)$. Give your answer in the form $y = mx + c$.
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PastPaper.workedSolution
First, find the midpoint, $M$, of the line segment $AB$:
Now, find the equation of the perpendicular line passing through the midpoint $(5, 3)$:
$$y - 3 = 1.5(x - 5)$$
$$y - 3 = 1.5x - 7.5$$
$$y = 1.5x - 4.5$$
PastPaper.markingScheme
M1 for finding either the midpoint $(5, 3)$ or the perpendicular gradient $1.5$ (or $\frac{3}{2}$) A1 for $y = 1.5x - 4.5$ or $y = \frac{3}{2}x - \frac{9}{2}$
PastPaper.question 16 · Medium Structured
4 PastPaper.marks
Solve the equation:
\(\frac{10}{x} - \frac{6}{x + 3} = 1\)
Show all your working.
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PastPaper.workedSolution
First, multiply the entire equation by the common denominator \(x(x + 3)\):
\(10(x + 3) - 6x = x(x + 3)\)
Expand both sides:
\(10x + 30 - 6x = x^2 + 3x\)
\(4x + 30 = x^2 + 3x\)
Rearrange the equation into standard quadratic form \(ax^2 + bx + c = 0\):
\(x^2 - x - 30 = 0\)
Factorise the quadratic expression:
\((x - 6)(x + 5) = 0\)
This gives the solutions:
\(x = 6\) or \(x = -5\)
PastPaper.markingScheme
M1: For multiplying through by the common denominator to obtain \(10(x + 3) - 6x = x(x + 3)\) or equivalent. M1: For expanding and simplifying to a three-term quadratic equation, e.g., \(x^2 - x - 30 = 0\). M1: For factorising their quadratic into two brackets, e.g., \((x - 6)(x + 5) = 0\), or correct substitution into the quadratic formula. A1: For both correct solutions \(x = 6\) and \(x = -5\).
PastPaper.question 17 · Medium Structured
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A rectangular garden has dimensions 12 metres by 8 metres. It is surrounded by a path of uniform width \(w\) metres. The total area of the garden and the path combined is \(165\text{ m}^2\).
Find the value of \(w\), showing all your working.
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PastPaper.workedSolution
The total length of the garden and the path combined is \(12 + 2w\) metres. The total width of the garden and the path combined is \(8 + 2w\) metres.
The total combined area is given by:
\((12 + 2w)(8 + 2w) = 165\)
Expand the brackets:
\(96 + 24w + 16w + 4w^2 = 165\)
\(4w^2 + 40w + 96 = 165\)
Rearrange into a standard quadratic form:
\(4w^2 + 40w - 69 = 0\)
Solve using the quadratic formula where \(a = 4\), \(b = 40\), and \(c = -69\):
Since the width \(w\) must be positive, we discard the negative solution.
Thus, \(w = 1.5\).
PastPaper.markingScheme
M1: For writing a correct expression for the combined dimensions, i.e., \((12 + 2w)\) and \((8 + 2w)\). M1: For setting up the area equation: \((12 + 2w)(8 + 2w) = 165\). A1: For expanding and simplifying to the quadratic equation \(4w^2 + 40w - 69 = 0\). A1: For solving the quadratic equation to get \(w = 1.5\) (accepting the rejection of the negative root).
PastPaper.question 18 · Medium Structured
4 PastPaper.marks
Solve the simultaneous equations:
\(y = 2x - 3\)
\(x^2 + xy = 6\)
Show all your working.
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PastPaper.workedSolution
Substitute the expression for \(y\) from the first equation into the second equation:
\(x^2 + x(2x - 3) = 6\)
Expand the term \(x(2x - 3)\):
\(x^2 + 2x^2 - 3x = 6\)
Combine like terms to form a quadratic equation:
\(3x^2 - 3x - 6 = 0\)
Divide the entire equation by 3 to simplify:
\(x^2 - x - 2 = 0\)
Factorise the quadratic:
\((x - 2)(x + 1) = 0\)
This gives the x-values:
\(x = 2\) or \(x = -1\)
Now, substitute these x-values back into the linear equation \(y = 2x - 3\) to find the corresponding y-values:
For \(x = 2\):
\(y = 2(2) - 3 = 1\)
For \(x = -1\):
\(y = 2(-1) - 3 = -5\)
So the solutions are \(x = 2, y = 1\) and \(x = -1, y = -5\).
PastPaper.markingScheme
M1: For substituting \(y = 2x - 3\) into the second equation to get \(x^2 + x(2x - 3) = 6\). A1: For simplifying to \(3x^2 - 3x - 6 = 0\) (or \(x^2 - x - 2 = 0\)). M1: For solving their quadratic equation to find two values of \(x\) (\(x = 2\) and \(x = -1\)). A1: For finding both corresponding \(y\) values correctly: \(y = 1\) when \(x = 2\) and \(y = -5\) when \(x = -1\) (or writing as coordinate pairs \((2, 1)\) and \((-1, -5)\)).
PastPaper.question 19 · Medium Structured
4 PastPaper.marks
In triangle \(ABC\), \(AB = 7\text{ cm}\), \(BC = 11\text{ cm}\) and angle \(ABC = 115^\circ\).
Calculate the size of angle \(BAC\). Give your answer correct to 1 decimal place.
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PastPaper.workedSolution
First, use the Cosine Rule to find the length of side \(AC\):
\(AC^2 = AB^2 + BC^2 - 2 \cdot AB \cdot BC \cdot \cos(ABC)\)
\(\sin A = 11 \cdot \frac{0.906308}{15.332} \approx 0.65022\)
\(A = \arcsin(0.65022) \approx 40.56^\circ\)
To 1 decimal place, angle \(BAC = 40.6^\circ\).
PastPaper.markingScheme
M1: For applying the Cosine Rule: \(AC^2 = 7^2 + 11^2 - 2(7)(11)\cos(115^\circ)\). A1: For calculating \(AC \approx 15.3\text{ cm}\) (or more precise, e.g., \(15.332\)). M1: For applying the Sine Rule: \(\frac{\sin(BAC)}{11} = \frac{\sin(115^\circ)}{15.33}\) (or using the Cosine Rule to find angle \(BAC\)). A1: For angle \(BAC = 40.6^\circ\) (or \(40.6\)).
PastPaper.question 20 · Medium Structured
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A ship sails from port \(P\) on a bearing of \(060^\circ\) for 15 km to point \(Q\). It then changes direction and sails on a bearing of \(130^\circ\) for 22 km to point \(R\).
Calculate the distance from \(P\) to \(R\). Give your answer in km correct to 3 significant figures.
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PastPaper.workedSolution
Let's first determine the interior angle \(PQR\) of triangle \(PQR\).
The bearing from \(P\) to \(Q\) is \(060^\circ\). Draw a North-South line at \(Q\). The angle from the South direction at \(Q\) pointing back to \(P\) is also \(060^\circ\) (alternate angles).
The bearing of \(R\) from \(Q\) is \(130^\circ\). The angle between the North line and the line \(QR\) is \(130^\circ\). The angle between the South direction and \(QR\) is \(180^\circ - 130^\circ = 50^\circ\).
To 3 significant figures, the distance is \(30.6\text{ km}\).
PastPaper.markingScheme
M1: For calculating the interior angle \(PQR = 110^\circ\). M1: For applying the Cosine Rule: \(PR^2 = 15^2 + 22^2 - 2(15)(22)\cos(110^\circ)\). A1: For evaluating \(PR^2 \approx 934.7\) (or \(935\)). A1: For \(PR = 30.6\text{ km}\) (accept \(30.6\)).
PastPaper.question 21 · Medium Structured
4 PastPaper.marks
In triangle \(XYZ\), \(XY = 8.5\text{ cm}\) and \(YZ = 12.4\text{ cm}\). The area of the triangle is \(40.5\text{ cm}^2\). Angle \(XYZ\) is an obtuse angle.
Calculate the length of \(XZ\), giving your answer in cm correct to 3 significant figures.
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PastPaper.workedSolution
First, find the angle \(XYZ\) (let's call it \(Y\)) using the area formula:
\(\text{Area} = \frac{1}{2} \cdot XY \cdot YZ \cdot \sin Y\)
To 3 significant figures, the length of \(XZ\) is \(19.0\text{ cm}\).
PastPaper.markingScheme
M1: For writing a correct equation for the area: \(0.5 \times 8.5 \times 12.4 \times \sin(Y) = 40.5\). A1: For calculating the obtuse angle \(Y \approx 129.8^\circ\) (or \(129.78^\circ\)). M1: For applying the Cosine Rule: \(XZ^2 = 8.5^2 + 12.4^2 - 2(8.5)(12.4)\cos(129.8^\circ)\). A1: For \(XZ = 19.0\text{ cm}\) (or \(19\)).
PastPaper.question 22 · Medium Structured
4 PastPaper.marks
On any given day, the probability that it rains is 0.3. When it rains, a local weather station correctly forecasts rain with a probability of 0.9. When it does not rain, the station incorrectly forecasts rain with a probability of 0.2.
Calculate the probability that it actually rains on a day when the station forecasts rain. Give your answer correct to 3 significant figures.
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PastPaper.workedSolution
Let \(R\) be the event that it rains, and \(F\) be the event that the weather station forecasts rain.
We are given:
\(P(R) = 0.3\)
\(P(R') = 0.7\)
\(P(F|R) = 0.9\)
\(P(F|R') = 0.2\)
We want to find the conditional probability \(P(R|F)\):
\(P(R|F) = \frac{P(R \cap F)}{P(F)}\)
First, find the probability of both rain and a forecast of rain:
To 3 significant figures, the probability is \(0.659\).
PastPaper.markingScheme
M1: For calculating \(P(\text{Rain} \cap \text{Forecast}) = 0.3 \times 0.9 = 0.27\). M1: For calculating \(P(\text{No Rain} \cap \text{Forecast}) = 0.7 \times 0.2 = 0.14\). A1: For the total probability of forecasting rain \(P(F) = 0.41\). A1: For finding the conditional probability \(\frac{27}{41}\) or \(0.659\) (accept answers rounding to \(0.659\)).
PastPaper.question 23 · Medium Structured
4 PastPaper.marks
Find the equation of the perpendicular bisector of the line segment joining the points \(A(-3, 8)\) and \(B(5, 2)\).
Give your answer in the form \(ay + bx = c\), where \(a\), \(b\), and \(c\) are integers.
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PastPaper.workedSolution
First, find the midpoint \(M\) of the line segment \(AB\):
Fourth, write the equation of the line passing through \(M(1, 5)\) with gradient \(\frac{4}{3}\):
\(y - 5 = \frac{4}{3}(x - 1)\)
Multiply the entire equation by 3 to clear the fraction:
\(3(y - 5) = 4(x - 1)\)
\(3y - 15 = 4x - 4\)
Rearrange the equation into the form \(ay + bx = c\):
\(3y - 4x = 11\)
PastPaper.markingScheme
M1: For finding the midpoint of \(AB\) as \((1, 5)\). M1: For finding the gradient of \(AB\) as \(-\frac{3}{4}\). M1: For finding the gradient of the perpendicular line as \(\frac{4}{3}\). A1: For the final equation \(3y - 4x = 11\) or any equivalent integer equation in the form \(ay + bx = c\) (e.g., \(4x - 3y = -11\)).
PastPaper.question 24 · Extended
4 PastPaper.marks
In a triangle \(ABC\), \(AB = 110\text{ m}\) and \(BC = 145\text{ m}\). The bearing of \(C\) from \(B\) is \(115^\circ\) and the bearing of \(A\) from \(B\) is \(215^\circ\). Calculate the distance \(AC\).
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PastPaper.workedSolution
First, find the angle \(ABC\) using bearings: \(\angle ABC = 215^\circ - 115^\circ = 100^\circ\). Next, apply the cosine rule to find \(AC\): \(AC^2 = AB^2 + BC^2 - 2 \cdot AB \cdot BC \cdot \cos(ABC)\). Substitute the values: \(AC^2 = 110^2 + 145^2 - 2 \cdot 110 \cdot 145 \cdot \cos(100^\circ)\). Simplify the expression: \(AC^2 = 12100 + 21025 - 31900 \cdot (-0.173648) = 33125 + 5539.38 = 38664.38\). Solve for \(AC\): \(AC = \sqrt{38664.38} \approx 196.63\text{ m}\). Giving the answer to 3 significant figures yields \(197\text{ m}\).
PastPaper.markingScheme
M1 for finding angle \(ABC = 100^\circ\) M1 for correct substitution into the cosine rule, e.g. \(110^2 + 145^2 - 2 \cdot 110 \cdot 145 \cdot \cos(100^\circ)\) A1 for intermediate evaluation \(38664\dots\) or \(\sqrt{38664\dots}\) A1 for final answer \(197\) or \(196.6\dots\)
PastPaper.question 25 · Extended
4 PastPaper.marks
Find the equation of the perpendicular bisector of the line segment joining the points \(A(2, -3)\) and \(B(6, 5)\). Give your answer in the form \(y = mx + c\).
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PastPaper.workedSolution
First, find the midpoint of the line segment \(AB\): \(\text{Midpoint } M = \left(\frac{2+6}{2}, \frac{-3+5}{2}\right) = (4, 1)\). Next, find the gradient of the line \(AB\): \(m_{AB} = \frac{5 - (-3)}{6 - 2} = \frac{8}{4} = 2\). The gradient of the perpendicular line is the negative reciprocal: \(m_{\perp} = -\frac{1}{2} = -0.5\). Now, use the gradient-intercept form \(y = mx + c\) with the midpoint \((4, 1)\) and the perpendicular gradient \(-0.5\): \(1 = -0.5(4) + c \Rightarrow 1 = -2 + c \Rightarrow c = 3\). Thus, the equation of the perpendicular bisector is \(y = -0.5x + 3\).
PastPaper.markingScheme
M1 for finding the gradient of \(AB\) as \(2\) M1 for finding the perpendicular gradient as \(-0.5\) (or negative reciprocal of their gradient) M1 for finding the midpoint of \(AB\) as \((4, 1)\) A1 for the correct equation \(y = -0.5x + 3\) or equivalent form \(y = -\frac{1}{2}x + 3\)
PastPaper.question 26 · Long Multi-step
15 PastPaper.marks
The diagram (not to scale) shows a quadrilateral plot of land \(ABCD\). \(AB = 85\text{ m}\), \(AD = 60\text{ m}\), and angle \(BAD = 110^\circ\).
(a) Show that \(BD = 120\text{ m}\), correct to the nearest metre. [4]
(b) The angle \(BCD = 42^\circ\) and angle \(CBD = 58^\circ\). Calculate the length of \(CD\). [4]
(c) Calculate the total area of the field \(ABCD\). [4]
(d) Calculate the shortest distance from \(A\) to the line \(BD\). [3]
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PastPaper.workedSolution
(a) Using the Cosine Rule in \(\triangle ABD\): \(BD^2 = AB^2 + AD^2 - 2 \cdot AB \cdot AD \cdot \cos(\angle BAD)\) \(BD^2 = 85^2 + 60^2 - 2 \cdot 85 \cdot 60 \cdot \cos(110^\circ)\) \(BD^2 = 7225 + 3600 - 10200 \cdot (-0.34202)\) \(BD^2 = 10825 + 3488.6 = 14313.6\) \(BD = \sqrt{14313.6} = 119.64\text{ m}\). Rounded to the nearest metre, \(BD = 120\text{ m}\).
(b) In \(\triangle BCD\), the sum of angles is \(180^\circ\). \(\angle BDC = 180^\circ - (42^\circ + 58^\circ) = 80^\circ\). Using the Sine Rule: \(\frac{CD}{\sin(58^\circ)} = \frac{BD}{\sin(42^\circ)} Using the more accurate value \)BD = 119.64\text{ m}\): \(CD = \frac{119.64 \cdot \sin(58^\circ)}{\sin(42^\circ)} = \frac{119.64 \cdot 0.84805}{0.66913} = 151.62\text{ m}\). To 3 significant figures, \(CD = 152\text{ m}\). (If using the given \(BD = 120\text{ m}\): \(CD = \frac{120 \cdot \sin(58^\circ)}{\sin(42^\circ)} = 152.08 \approx 152\text{ m}\)).
(c) Total Area = \(\text{Area of } \triangle ABD + \text{Area of } \triangle BCD\) \(\text{Area of } \triangle ABD = \frac{1}{2} \cdot AB \cdot AD \cdot \sin(110^\circ) = \frac{1}{2} \cdot 85 \cdot 60 \cdot \sin(110^\circ) = 2396.2\text{ m}^2\). \(\text{Area of } \triangle BCD = \frac{1}{2} \cdot BD \cdot CD \cdot \sin(\angle BDC) = \frac{1}{2} \cdot 119.64 \cdot 151.62 \cdot \sin(80^\circ) = 8932.6\text{ m}^2\). Total Area = \(2396.2 + 8932.6 = 11328.8 \approx 11300\text{ m}^2\) (to 3 s.f.). (If using \(BD = 120\text{ m}\) and \(CD = 152\text{ m}\): \(\text{Area of } \triangle BCD = \frac{1}{2} \cdot 120 \cdot 152 \cdot \sin(80^\circ) = 8981.5\text{ m}^2\). Total Area = \(2396.2 + 8981.5 = 11377.7 \approx 11400\text{ m}^2\) (to 3 s.f.)). All values in range \([11300, 11400]\) are correct and accepted.
(d) The shortest distance from \(A\) to the line \(BD\) is the perpendicular height, \(h\), of \(\triangle ABD\) with base \(BD\). \(\text{Area of } \triangle ABD = \frac{1}{2} \cdot BD \cdot h\) Using the accurate value \(BD = 119.64\text{ m}\): \(2396.2 = \frac{1}{2} \cdot 119.64 \cdot h \implies h = \frac{2 \cdot 2396.2}{119.64} = 40.05 \approx 40.1\text{ m}\). (If using the given value \(BD = 120\text{ m}\): \(2396.2 = \frac{1}{2} \cdot 120 \cdot h \implies h = \frac{2 \cdot 2396.2}{120} = 39.94 \approx 39.9\text{ m}\). Alternatively, using right-angled trigonometry: \(\sin(\angle ADB) = \frac{85 \cdot \sin(110^\circ)}{119.64} \implies \angle ADB = 41.87^\circ\). \(h = 60 \cdot \sin(41.87^\circ) = 40.05 \approx 40.1\text{ m}\)). All values in range \([39.9, 40.1]\) are accepted.
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(a) [4 marks] M1: For correct substitution into the Cosine Rule: \(85^2 + 60^2 - 2 \cdot 85 \cdot 60 \cdot \cos(110)\). A1: For correct evaluation of parts: \(7225 + 3600 - (-3488.6)\) or \(14313.6\). A1: For \(BD = 119.64...\) A1: For final rounding statement concluding that \(BD = 120\text{ m}\) to the nearest metre.
(b) [4 marks] M1: For finding \(\angle BDC = 180 - 42 - 58 = 80^\circ\). M1: For correct substitution into the Sine Rule: \(\frac{CD}{\sin(58)} = \frac{BD}{\sin(42)}\). A1: For rearranging to find \(CD\) using either \(119.64\) or \(120\). A1: For \(CD = 152\text{ m}\) (accept range \([151.6, 152.1]\)).
(c) [4 marks] M1: For correct method to find the area of \(\triangle ABD\), e.g., \(\frac{1}{2} \cdot 85 \cdot 60 \cdot \sin(110)\) (or \(2396\)). M1: For correct method to find the area of \(\triangle BCD\), e.g., \(\frac{1}{2} \cdot BD \cdot CD \cdot \sin(80)\). A1: For one correct triangle area calculated: \(2396\) or \(8933\) (or \(8982\)). A1: For total area in the range \([11300, 11400]\).
(d) [3 marks] M1: For recognizing that the shortest distance is the perpendicular height of \(\triangle ABD\). M1: For setting up an equation, e.g., \(\frac{1}{2} \cdot 119.64 \cdot h = 2396\) or \(h = 60 \cdot \sin(41.87)\). A1: For answer in the range \([39.9, 40.1]\).
PastPaper.question 27 · Long Multi-step
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A delivery van travels a distance of 180 km from warehouse A to warehouse B at an average speed of \(x\) km/h. On the return journey from B to A, the average speed of the van is reduced by 15 km/h due to heavy traffic.
(a) Write down an expression, in terms of \(x\), for the time taken, in hours, for: (i) the journey from A to B, [1] (ii) the return journey from B to A. [1]
(b) The total time for the two journeys is 7.5 hours. Show that \(x^2 - 63x + 360 = 0\). [5]
(c) Solve the equation \(x^2 - 63x + 360 = 0\), giving your answers correct to 2 decimal places. Show all your working. [4]
(d) Find the time taken for the return journey from B to A. Give your answer in hours and minutes, to the nearest minute. [4]
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(a)(i) Time taken from A to B = \(\frac{180}{x}\) hours.
(a)(ii) Time taken from B to A = \(\frac{180}{x-15}\) hours.
(b) Since the total time is \(7.5\) hours: \(\frac{180}{x} + \frac{180}{x-15} = 7.5\) Divide both sides by \(7.5\): \(\frac{24}{x} + \frac{24}{x-15} = 1\) Multiply by the common denominator, \(x(x - 15)\): \(24(x - 15) + 24x = x(x - 15)\) \(24x - 360 + 24x = x^2 - 15x\) \(48x - 360 = x^2 - 15x\) Rearrange to form a quadratic equation: \(x^2 - 15x - 48x + 360 = 0\) \(x^2 - 63x + 360 = 0\) (as required).
(d) For the return journey speed to be positive, we must have \(x - 15 > 0\), which implies \(x > 15\). Thus, we reject \(x = 6.36\) and select \(x = 56.64\) km/h. Return speed = \(56.64 - 15 = 41.64\text{ km/h}\). Time taken for return journey = \(\frac{180}{41.64} = 4.32276\text{ hours}\). Converting the fractional part to minutes: \(0.32276 \times 60 = 19.36\text{ minutes}\). Therefore, the time taken is 4 hours and 19 minutes (to the nearest minute).
PastPaper.markingScheme
(a)(i) [1 mark] B1: For \(\frac{180}{x}\).
(a)(ii) [1 mark] B1: For \(\frac{180}{x-15}\).
(b) [5 marks] M1: For setting up the sum of times equation: \(\frac{180}{x} + \frac{180}{x-15} = 7.5\). M1: For removing algebraic fractions by multiplying by the common denominator \(x(x-15)\). M1: For expanding brackets correctly, e.g., \(24(x-15)\) as \(24x - 360\) or \(180(x-15)\) as \(180x - 2700\). A1: For a correct intermediate step, e.g., \(48x - 360 = x^2 - 15x\) or \(360x - 2700 = 7.5x^2 - 112.5x\). A1: For fully correct algebraic manipulation leading to \(x^2 - 63x + 360 = 0\) with no errors seen.
(c) [4 marks] M1: For identifying coefficients and substituting into the quadratic formula (allow 1 sign error). A1: For finding the discriminant term correctly: \(\sqrt{2529}\) or \(50.29\). A1: For \(x = 56.64\). A1: For \(x = 6.36\).
(d) [4 marks] M1: For rejecting \(x = 6.36\) with a valid reason, e.g., \(x - 15 > 0\), or selecting \(x = 56.64\). M1: For calculating the return journey speed or time, e.g., \(56.64 - 15 = 41.64\) or \(\frac{180}{41.64}\). A1: For \(4.32...\) hours. A1: For converting to \(4\text{ hours } 19\text{ minutes}\) (accept \(4\text{ h } 19\text{ m}\)).