Four operations with integers, decimals, and fractions：練習問題

A rectangular rug has a length of \(2.5\text{ m}\) and a width of \(180\text{ cm}\). What is the area of the rug in square metres?

Evaluate the following expression: \( 5.4 \div [ ( 1.2 + 0.3 ) \times 0.6 ] - 1.5 \).

A rectangular tank is \(2\frac{1}{4}\text{ m}\) long, \(1\frac{1}{3}\text{ m}\) wide, and \(0.8\text{ m}\) high. If the tank is \(\frac{3}{4}\) full of water, find the volume of water in cubic metres.

Calculate the value of \( 4\frac{1}{5} + 2\frac{2}{3} - 1\frac{1}{2} \).

A rectangular container with a base area of \(200\text{ cm}^2\) is filled with water to a depth of \(12\text{ cm}\). If a metal sphere with a volume of \(800\text{ cm}^3\) is placed into the container and completely submerged, what is the new depth of the water in centimetres?

Calculate the value of \( \left( 4\frac{2}{3} - 1.5 \right) \div \frac{1}{6} + 2 \). Express the result as a whole number.

A shopkeeper bought \(25\text{ kg}\) of flour. He used \(3\frac{3}{4}\text{ kg}\) on Monday and \(2.4\text{ times}\) that amount on Tuesday. How many kilograms of flour were left after Tuesday?

Calculate the value of the following expression:
\( \left( 3\frac{1}{2} - 1.75 \right) \div \frac{3}{4} + 2.4 \times 5 \)
(a) Show the steps of the calculation.
(b) If the result is multiplied by \(-2\), what is the final value?
(c) Express the final value from (b) as a fraction in its simplest form.

A construction project requires mixing different materials by weight.
(a) Evaluate: \( 15.6 \div (2\frac{2}{5} \times 0.5) + 4\frac{1}{8} \).
(b) A worker has a bag of cement weighing \( 25.5 \text{ kg} \). He uses \( \frac{1}{3} \) of it for the first floor and \( 4.2 \text{ kg} \) for the second floor. What percentage of the original bag is left?
(c) If the remaining cement is distributed equally into 4 small containers, how many kilograms will be in each container? Express your answer as a decimal.