Page 133 - Start Up Mathematics_3

2. Write the time shown in the clock in two ways.

(a) (b) (c)
12 12 12
11 1 11 1 11 1
10 2 10 2 10 2
9 3 9 3 9 3
8 4 8 4 8 4
7 5 7 5 7 5
6 6 6

9:20

20 minutes past 9

(d) (e) (f)
12 12 12
11 1 11 1 11 1
10 2 10 2 10 2
9 3 9 3 9 3
8 4 8 4 8 4
7 5 7 5 7 5
6 6 6

Duration of Time
A Challenge!
Duration of time means the time passed between Arushi sat down to study
two events. For example, Raj leaves home at 7 o’clock at 5:30 in the evening.
in the morning. He reaches his school at 8 o’clock. She studied for 1 hour 30
It takes Raj 8 – 7 = 1 hour to reach school. So, the minutes. When did she
duration of time is 1 hour. finish her studies?

Calculating Time

We already know that there are 24 hours in one day and each hour has 60 minutes.
Also there are 60 seconds in one minute. Let’s use this knowledge to calculate time.
Look at the given example.

Example 1: Calculate the number of hours in 4 days.

Solution: Hours in 1 day = 24

Hours in 4 days = 24 × 4 = 96

Thus, there are 96 hours in 4 days.

125