Question

The ratio between the radius of two wheels is 4:5. Then, the ratio of their circumference is .

• A. 3:5
• B. 4:5
• C. 1:2
• D. 5:4

Answer 1

The correct option is B 4:5

$Circumferenceofcircle=2\times \pi \times rr1:r2=4:5c1:c2=2\times \pi \times r1:2\times \pi \times r2=r1:r2$
Therefore, c1:c2 = 4:5