Question

Two person do the same amount of work in 10 s and 20 s respectively. What is the ratio of the power used by the first person to that by the second person

Answer 1

let the work be x
power ratio = x/10 : x/20

x will cancel by cross multiplication we will get

20 : 10

= 2:1

Answer 2

consider A as work
then working of 1st person per second is- A/10
llly second person per second is- A/20
taking ratio

A/20=A/10
after cancellation of similar terms will be
20:10
and now cancel zeros you get answer is
2:1