Pearson Edexcel International GCSE (9–1) · MATHEMATICS A · Unit
Unit 2
105 practice questions
Topics covered
Practice questions
91–100 of 105
Question 91
4 marks · Easy
Answer and see the solution →A circle has a radius of 6 cm. Use the formula to calculate its circumference. Then, use your answer to work out the probability that a point chosen at random on the circle's circumference lies in the first quarter (a 90° arc).
(a)[2 marks]Find the circumference of the circle. Use .
(b)[2 marks]What is the probability that a randomly chosen point on the circumference lies in the first quarter (90°) of the circle? Give your answer as a fraction.
Question 92
4 marks · Easy
Answer and see the solution →a) Simplify the following using laws of indices: 5^3 × 5^2.
b) A rectangle has length 10 cm and width 3 cm. Work out its area. Give your answer in standard form.
(a)[2 marks]Simplify the following using laws of indices: 5^3 × 5^2.
(b)[2 marks]A rectangle has length 10 cm and width 3 cm. Work out its area. Give your answer in standard form.
Question 93
4 marks · Easy
Answer and see the solution →A physicist records a measurement in standard form as metres. She then substitutes this distance into the equation , where m/s and is the time in seconds.
(a)[1 mark]Write metres as an ordinary number.
(b)[3 marks]Work out the value of , giving your answer in standard form.
Question 94
4 marks · Easy
Answer and see the solution →The heights (in metres) of four plants are shown below:
Plant Height (m) A 1.32 B 1.18 C 1.40 D 1.26 A fifth plant is measured at 1.34 m. The total height of all five plants is recorded. The mean height is also calculated.
(a)[2 marks]Work out the total height of all five plants.
(b)[2 marks]Calculate the mean height of the five plants. Give your answer to 2 decimal places.
Question 95
4 marks · Normal
Answer and see the solution →A circular swimming pool has a diameter of 16 m. Water is pumped into the pool at a constant rate. The following table shows the depth of water after different times:
(a)[1 mark]Depth of water over time Time (minutes) Depth (m) 10 0.8 20 1.6 30 2.4 40 ? (b)[2 marks]Calculate the area of the surface of the pool. Give your answer in standard form.
(c)[1 mark]Express the answer from part (b) as an ordinary number.
Question 96
4 marks · Normal
Answer and see the solution →A rectangle has a length of 4x cm and a width of 2x cm. The area of the rectangle is equal to 72 cm².
(a)[1 mark]Write down an equation in terms of x for the area of the rectangle.
(b)[2 marks]Solve your equation to find the value of x.
(c)[1 mark]Calculate the perimeter of the rectangle.
Question 97
4 marks · Normal
Answer and see the solution →Amira draws a circle with a radius of 5 cm.
(a)[2 marks]Calculate the area of the circle. Give your answer correct to 1 decimal place.
(b)[2 marks]Amira increases the radius by 20%. What is the new area of the circle, correct to 1 decimal place?
Question 98
4 marks · Normal
Answer and see the solution →The diameter of a circular pond is 14 m. Water is being added at a rate that increases the depth from 0.9 m to 1.15 m over 5 hours.
(a)[1 mark]Write the formula for calculating the volume of water added, using π, diameter and change in depth.
(b)[2 marks]Calculate the volume of water added to the pond over 5 hours. Give your answer to the nearest whole number.
(c)[1 mark]Express your answer to part (b) in standard form.
Question 99
4 marks · Normal
Answer and see the solution →A circle has a diameter of 18 cm.
a) Work out the radius of the circle.
b) The area of the circle is decreased by 10%. Work out the new area of the circle. Give your answer in cm² to 2 decimal places.
(a)[1 mark]Work out the radius of the circle.
(b)[3 marks]The area of the circle is decreased by 10%. Work out the new area of the circle. Give your answer in cm² to 2 decimal places.
Question 100
5 marks · Normal
Answer and see the solution →1. Scientists measured the mass of a grain of rice as 0.000028 kg. In a laboratory, a student investigates a relationship using the formula , where is mass in kilograms and m/s.
(a)[1 mark]Express the mass of one grain of rice in standard form.
(b)[2 marks]Calculate and write your answer in standard form.
(c)[2 marks]Using your answers to (a) and (b), work out the value of for one grain of rice. Give your answer in standard form.