Page 162 - ICSE Math 4

Example 6: Convert 156 seconds to minutes and seconds. 2  minutes
1
Solu on: We know that 1 s = min. 60 156
60
156 –120
Thus, 156 = min. 36  seconds
60
So, 156 = 2 min 36 s.

Example 7: Convert 6,296 seconds to hours, minutes and seconds. 104  minutes
60 6296
Solu on: Step 1: Convert seconds to minutes.
–60
1
1 s = min 29
60 – 00
6296
Thus, 6,296 s = min. 296
60
So, 6,296 s = 104 min 56 s. 240

Step 2: Convert minutes to hours. 56  seconds

1
1 min = h 1  hour
60 104
Thus, 104 min = h 60 104
60 – 60
So, 104 min = 1 h 44 min
44  minutes
Step 3: Write the hours, minutes and seconds together.

So, 6,296 s = 1 h 44 min 56 s.

Exercise 12.3

1. Convert the following to hours.
(a) 9 days (b) 14 days 16 hours (c) 1 week 2 hours

2. Convert the following to days and hours.

(a) 96 hours (b) 106 hours (c) 169 hours (d) 248 hours

3. Convert the following to minutes.
(a) 5 hours (b) 8 hours 10 minutes (c) 21 hours 30 minutes

4. Convert the following to hours and minutes.

(a) 245 minutes (b) 528 minutes (c) 714 minutes (d) 1,296 minutes

5. Convert the following to seconds.

(a) 5 minutes (b) 16 minutes 20 seconds
(c) 45 minutes 58 seconds (d) 10 minutes 12 seconds

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