Stage 8 - Q1 - 2 marks
Find the circumference in terms of \(\pi\).
Hint
The diameter is already given.
Stage 8 - Q2 - 2 marks
Find the circumference in terms of \(\pi\).
Hint
Double the radius before multiplying by \(\pi\).
Stage 8 - Q3 - 2 marks
Find the circumference to 2 decimal places.
Hint
Use the calculator \(\pi\) key and round only the final result.
Stage 8 - Q4 - 2 marks
A circle has circumference \(26\pi\) cm. Find its radius.
Hint
Circumference is \(2\pi\) times the radius.
Stage 8 - Q5 - 2 marks
A wheel has diameter 35 cm. How far does it travel in 40 complete turns? Give metres in terms of \(\pi\).
Hint
Convert the unit before multiplying.
Stage 8 - Q6 - 2 marks
A circular border is \(18\pi\) m long. Find the diameter and radius.
Hint
Use the inverse of the circumference formula.
Stage 8 - Q7 - 3 marks
Circle A has radius 3.2 cm and circle B has diameter 7 cm. Which circumference is larger, and by how much in terms of \(\pi\)?
Hint
A radius and a diameter cannot be compared directly.
Stage 8 - Q8 - 3 marks
A wire forms a circle of radius 12 cm. It is cut into three equal pieces, each made into a circle. Find each new radius.
Hint
The wire length is a circumference, not an area.
Stage 8 - Q9 - 4 marks
Two circular loops use a total of \(42\pi\) cm of wire. Their radii differ by 3 cm. Find both radii.
Hint
Express the larger radius as \(r+3\).
Stage 8 - Q10 - 5 marks
Challenge: a wheel of diameter 72 cm rolls without slipping for \(30\pi\) m. Find the number of complete turns and the angle turned in the remaining partial turn.
Hint
Keep \(\pi\) exact and use the same length unit throughout.