Page 131 - Start Up Mathematics_3

Seconds

Seconds is another unit used to measure time. It is shorter than a minute. There are

60 seconds in one minute.

1 minute = 60 seconds

Some watches and clocks have the second hand. It is thinner
and longer than the hour and minute hands. It moves very 11 12 1
fast and covers one full circle across the clock face in 60 10 2
seconds or one minute. Quarter Quarter
9 to Past 3
To read time, we divide the clock into two halves—one part is Half Past 4

from 12 to 6 and the other part is from 6 to 12. In the given 8 7 5
figure, the dotted line divides the clock into two halves. 6
• When the minute hand is on the right side of

the dotted line, we read the time as minutes Remember
past a given hour. Minutes are always written
• When the minute hand is on the left side of the with 2 digits.
dotted line, we read the time as minutes to the 4:5  4:05 
next hour.

Look at the given examples.

1. 11 12 1 Here, the minute hand is at 1 and the hour hand has just
10 2
passed the 4 mark.
9 3
8 4 1 × 5 = 5 minutes

7 6 5 So, the time is 4:05 or 5 minutes past 4.

2. 11 12 1 The minute hand is at 4 and the hour hand has just passed
10 2 the 11 mark.
9 3
8 4 4 × 5 = 20 minutes

7 6 5 So, the time is 11:20 or 20 minutes past 11.

3. 12 The minute hand is at 7 and the hour hand has passed 2
11 1 and is about to reach 3.
10 2
9 3 (The minute hand is now on left side of the dotted line.)
8 7 5 4 7 × 5 = 35 minutes
6
So, the time is 2:35 or 35 minutes past 2.

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