Page 124 - Math Skill - 4

122 Maths

Let’s Attempt

Example 1: Meena left her house for school at 7:05 a.m. and reached school at 7:45 a.m. How
much time did she take to reach school from her house?
Solution: Time taken = 7:45 a.m. – 7:05 a.m.

= 45 minutes – 5 minutes = 40 minutes
Thus, Meena took 40 minutes to reach her school.

Example 2: Harshit sleeps at 10:20 p.m. and gets up next morning after 8 hours 10 minutes.
At what time did he get up?
Solution: 8 hours after 10:20 p.m. is 6:20 a.m.
Adding 10 more minutes to it, we get 6:30 a.m.

Thus, Harshit got up at 6:30 a.m.

Example 3: Mohit’s school starts at 7:50 a.m. and closes at 1:30 p.m. How long does the school
work?
Solution: Time from 7:50 a.m. to 8:00 a.m. = 10 minutes
Time from 8:00 a.m. to 1:00 p.m. = 5 hours
Time from 1:00 p.m. to 1:30 p.m. = 30 minutes
Thus, total time = 5 hours + 10 minutes + 30 minutes
= 5 hours 40 minutes

Reading the Second Hand
We already know about the two hands (hour hand and minute hand) of a clock. Apart from
these two hands, some clocks also have a third hand. It is the thinnest and the fastest moving
among all the three hands. We call it the second hand.

11 12 1 Second hand goes round the clock
once in every minute. We can
10 2
say that the second hand takes
9 3 one minute (60 seconds) when it
8 4 Second hand covers all the 60 divisions or ticks
7 6 5 in the clock.

Look carefully at the following clocks and study the time shown by each.

11 12 1 11 12 1 11 12 1
10 2 10 2 10 2
9 3 9 3 9 3

8 4 8 4 8 4
7 6 5 7 6 5 7 6 5

20 minutes 5 seconds 55 minutes 45 seconds 40 minutes 50 seconds
past 2 or 2:20:05 past 12 or 12:55:45 past 4 or 4:40:50