It is important to know that there are:

 

60 seconds in 1 minute

and

60 minutes in 1 hour

 

This means that there are:

 

30 seconds in ½ minute

15 seconds in ¼ minute

45 seconds in ¾ minute

 

30 minutes in ½ hour

15 minutes in ¼ hour

45 minutes in ¾ hour

 

Got all that?

 

 

Example 1

Jack takes 5¼ minutes to learn his capital cities.

How many seconds is this?

 

 

Answer

1 minute = 60 seconds.

½ minute = 30 seconds.

¼ minute = 15 seconds.

5¼ minutes = 5 × 60 + 15 = 300 + 15 = 315 seconds.

 

Example 2

Ahmed starts work at 9 a.m. and finishes at 4:30 p.m.

For how many minutes is he at work?

 

Answer

From 9 a.m. to 4 p.m. is 7 hours so Ahmed is at work for 7½ hours.

1 hour = 60 minutes.

½ hour = 30 minutes.

 

7½ hours = 7 × 60 + 30 = 420 + 30 = 450 minutes.

 

 

Let's have a go at some problems of our own to solve.