Answers

2016-01-12T21:55:43+05:30
8(45)=360
9(x)=360
so,
x=360/9
=40
each period is of 40 min.
1 4 1
2016-01-12T21:59:35+05:30
It can be solved by ratio and proportion
Old time
Periods  : 8
Duration of Period : 45
New Time
Periods = 9
Duration of Period = x

As the total time is same
⇒ 8 * 45 = 9 * x
∴ x = 40

So when there are 9 periods each period will last for 40 minutes

Hope you like it ;)
0
try improve your english while answering.
sorry to say