Page 333 - Math Smart - 7
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@ A movie starts at 3.45 p.m. and ends at 5.30 p.m. How long was the movie?
Solution
Write both times in the 24-hournotation. Subtract the minutes.
1 Start time: 15 45 ^ 17 30
End time: 17 30 -1545
As 45 is greater than 30, you need to convert an hour into minutes.
5 Reduce the hours by 1 hour, and add 60 minutes to 30 minutes.
16 90
-15 45
Subtract the hours.
T 16 90
-1545
1 45
The movie was 1 h 45 min long.
Example 7
Find the time duration from
a) 10 00 to 14 20, b) 0045 to 11 15,
c) 12 25 to 17 10, and d) 11 45 to 22 05.
Solution
a) Draw a time line from 10 00 to 14 20.
14 20
10 00
10 00 14 00 14 20 4 20
The time duration from 10 00 to 14 20 is 4 h 20 min.
b) Draw a time line from 00 45 to 11 15.
0 75
00 45
10 30
00 45 10 45 11 15
The time duration from 00 45 to 11 15 is 10 h 30 min.
Draw a time line from 12 25 to 17 10.
6 70
I^Kf
12 25
4 45
12 25 16 25 17 10
The time duration from 12 25 to 17 10 is 4 h 45 min.
