Question

A child' s heart beats 360 in 5 minutes , how many times does it beat in 1 hour ?

Answer 1

5 min = 360 beats

1 min = 360/5 =72 beats---(1)

1 hr = 60 min
= 60* 72 beats[ from (1)]
= 4320 beats

Answer 2

Given : heart beats 360 in 5 min
∴ In 1 min = 360/5
                 = 72 times
1 hour = 60 min 
∴ Heart beats in 1 hour = 60 *72
                                      = 4320 times