The minute hand of a watch is 3 cm long. How far does its tip move in 25 minutes? [use `pi=3.14`]

Explanation

A minute hand takes one revolution in 60 minutes.
`therefore` In 60 minutes angle subtended at the center `=2pi`
In 25 minutes angle at the center `=(2pi)/(60) xx 25`
`=5/6 pi`
Hence, the distance travelled, `l=rtheta=3 xx 5/6 pi`
`=5/2 xx 3.14`
`=7.85` cm