Areas Related to Circles MCQs

Q1. How many revolutions does a wheel of radius 14 cm make to cover 1760 cm (pi = 22/7)?

• A.21
• B.125
• C.20
• D.88

Answer: C. 20

Q2. How many revolutions does a wheel of radius 14 cm make to cover 4400 cm (pi = 22/7)?

• A.50
• B.51
• C.314
• D.88

Answer: A. 50

Q3. How many revolutions does a wheel of radius 21 cm make to cover 2640 cm (pi = 22/7)?

• A.132
• B.20
• C.21
• D.125

Answer: B. 20

Quick parse - a typical math numerical. The data on the table: 21 cm, 2640 cm. We are after How many revolutions does a wheel of radius 21 cm make to cover 2640 cm (pi = 22/7)?. Tool of choice - hence the answer = 20. Rearrange it for the unknown before substituting. Numbers in: hence the answer = 20. Common-sense check: draw the relevant radii and use the fact that the tangent _|_ radius at the contact point. Lock in option B) 20. Trap-watch: option A) '132' doesn't hold - Wrong: uses an incorrect intermediate value; option C) '21' is wrong because Wrong: a step was skipped or HCF/LCM swapped.