Question

A water wheel makes 28 revolutions in 90 seconds. how many revolutions can it make in 4 minutes?

Answer 1

90 seconds = 1.5 minutes
1.5 minutes = 28 revolutions
Revolutions in 1 minute = 28/1.5 = 18.67 revolutions

Revolutions in 4 minutes = 18.67*4
= 74.7 (approx.) revolutions

Answer 2

Explanation:

Alright, lets get started.

A water wheel makes revolutions 28 in 90 seconds.

We are asked to find number of revolutions in 4 minutes.

lets make 4 minutes into seconds

4 minutes =
`4*60=240 seconds`

In 90 seconds, the revolutions are = 28

So, in 1 second, the revolutions are =
`(28)/(90)`

So, in 240 seconds, the revolutions are =
`(28)/(90)*240`

So the revolutions are = 74.67 revolutions

It means, in 4 minutes, the numbers of revolutions are 74.67 . : Answer

Hope it will help :)