Pearson Edexcel IGCSE · Mathematics (Specification B)

Number: Practice Questions

5 multiple-choice questions marked as you go, and 5 written questions with worked solutions. All on Number.

10 questions22 marksFree, no account

Question 1

1 mark

Work out the value of \( 27^{\frac{2}{3}} \).

Question 2

1 mark

Simplify fully the expression \( (64a^{12}b^{-6})^{\frac{1}{3}} \).

Question 3

1 mark

A car travels a distance of \( 120 \text{ km} \), measured to the nearest \( 10 \text{ km} \). The time taken is \( 1.5 \text{ hours} \), measured to the nearest \( 0.1 \text{ hour} \). Calculate the lower bound for the average speed of the car, giving your answer to 2 decimal places.

Question 4

1 mark

Divide £\( 120 \) in the ratio \( 3 : 5 \). Find the value of the larger share.

Question 5

1 mark

The number of bacteria in a culture is given by the formula \(N = 500 \times 2^{t}\), where \(t\) is the time in hours. Calculate the time \(t\) when the number of bacteria reaches 16,000.

Question 6

2 marks

Simplify the expression \(\frac{10}{\sqrt{5}}\) by rationalising the denominator. Give your answer in the form \(a\sqrt{5}\).

Write your answer out first, then check it against the worked solution.

Question 7

3 marks

Calculate the value of \( \left( \frac{64}{27} \right)^{-\frac{2}{3}} \times 2^2 \). Show your working clearly.

Write your answer out first, then check it against the worked solution.

Question 8

5 marks

The distance between two stars is \( 8.64 \times 10^{13} \text{ km} \). A spacecraft travels at a constant speed of \( 4.8 \times 10^4 \text{ km/h} \). Calculate the time it would take for the spacecraft to travel between the stars. Give your answer in years, assuming \( 1 \text{ year} = 365 \text{ days} \). Give your answer in standard form to 3 significant figures.

Write your answer out first, then check it against the worked solution.

Question 9

3 marks

A large water reservoir contains \(4.8 \times 10^7\) liters of water. During a drought, the water level decreases by \(1.2 \times 10^6\) liters every day for 15 days.

(a) Calculate the total amount of water lost over the 15 days, giving your answer in standard form.
(b) Calculate the volume of water remaining in the reservoir after 15 days. Give your answer in the form \(a \times 10^n\) where \(1 \le a < 10\) and \(n\) is an integer.

Write your answer out first, then check it against the worked solution.

Question 10

4 marks

Three security lights are set to flash at different regular intervals. Light A flashes every \( 15 \) seconds, Light B flashes every \( 18 \) seconds, and Light C flashes every \( 24 \) seconds. At \( 20:00 \), all three lights flash at the same time.
(a) Find the next time that all three lights will flash at the same time.
(b) Calculate the total number of times all three lights will flash together between \( 20:00 \) and \( 21:00 \) inclusive.

Write your answer out first, then check it against the worked solution.

* The content provided by thinka is generated by AI and may not always be accurate or up-to-date. Please use it as a supplementary resource and verify with official materials.

You've seen the model answer. Now get yours marked.

This page can show you how a good answer looks. It cannot tell you what your answer was missing. thinka marks your written work against the real mark scheme in about 15 seconds.

Get My Answers Marked Back to the notes

Want more questions like these? Get a fresh set on this topic, graded as you go.