The radius of the wheel of a bus is 140 cms and the speed of the bus is 66 km/h, then the r.p.m. (revolutions per minutes)of the wheel is Choose the correct choice from the following options
A) 125
B) 250
C) 300
D) 330
E) none of these

Rationale: "radius of the wheel of bus = 140 cm . then , circumference of wheel = 2 ï € r = 280 ï € = 880 cm distance covered by bus in 1 minute = 66 â  „ 60 ã — 1000 ã — 100 cms distance covered by one revolution of wheel = circumference of wheel = 880 cm â ˆ ´ revolutions per minute = 6600000 / 60 ã — 880 = 125 answer a"
Answer: A