Fraction arithmetic and exact answers
3 exam-style questions. Answers and the mark for each step are on the last page.
- Question 1
Answer each part without a calculator.
(a) Work out of .
(b) A circle has an area of . A sector is of the circle. Work out the area of the sector. Give your answer in terms of .
- Question 2
A charity has 72 badges. It sells one quarter in the morning, then two thirds of the remaining badges in the afternoon.
(a) How many badges remain unsold?
(b) What fraction of the original badges was sold altogether?
- Question 3
A water tank is full. After litres are used, the tank is full.
(a) Work out the capacity of the tank, in litres.
(b) Next, of the water left in the tank is used. What fraction of the tank is now full?
Answers and marks
Question 1
(a)
- M1 Finding .
- A1 The correct answer, .
(b)
- M1 Writing .
- A1 The correct answer, .
Question 2
(a)
- P1 Find the quantity left after the first sale.
- P1 One third of that remainder survives the second sale.
- A1 Correct answer:
(b)
- P1 Compare the total sold with the original quantity.
- A1 Correct answer:
Question 3
(a) litres
- P1 Finding the fraction used, .
- P1 Setting of the capacity equal to 42, or finding .
- A1 The correct answer, litres.
(b)
- M1 Finding of , or finding the litres left out of .
- A1 The correct answer, .