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\\October 31, 2023 4:02 PM Bharat Arora P-5 Reader _________________________ Date: ___________________

example 3: Subtract 22 minutes 32 seconds from 30 minutes 18 seconds.

Solution: Write the time in columns and then subtract by following the given steps:
Step 1: Subtract the seconds.

Since 18 seconds < 32 seconds,

so, regroup minutes and seconds.
That is, borrow 1 minute = 60 seconds to seconds.

So, 30 minutes 18 seconds min s

= 29 minutes 60 seconds + 18 seconds 29 78
= 29 minutes 78 seconds 30 18
– 22 32
Now, 78 seconds – 32 seconds = 46 seconds 7 46

Step 2: Subtract the minutes.

29 minutes – 22 minutes = 7 minutes
Thus, the difference is equal to 7 minutes and 46 seconds. h min

example 4: Subtract 4 hours 44 minutes from 6 hours 14 minutes: 5 74

Solution: Following the steps similar to Example 3, we get the 6 14
difference of 6 hours 14 minutes and 4 hours 44 minutes – 4 44

= 1 hour 30 minutes. 1 30

Practice time 12e

1. Add the following:

(a) 35 minutes 38 seconds and 18 minutes 17 seconds

(b) 24 minutes 18 seconds and 5 minutes 20 seconds

(c) 28 minutes 38 seconds and 29 minutes 40 seconds

(d) 15 minutes 30 seconds and 30 minutes 35 seconds

(e) 16 hours 35 minutes 10 seconds and 25 hours 16 minutes 20 seconds.

(f) 100 hours 45 minutes 56 seconds and 5 hours 19 minutes 12 seconds.

2. Find the difference:

(a) 25 hours 24 minutes and 10 hours 9 minutes.

(b) 24 hours 38 minutes and 9 hours 40 minutes.

(c) 10 minutes 6 seconds and 5 minutes 26 seconds.

(d) 24 hours 40 minutes 10 seconds and 4 hours 56 minutes 16 seconds.

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