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(d) An express train left Vadodara at 4:40 p.m. on Monday and reached Guwahati on
Thursday at 12:30 p.m. Find the total duration of the journey.

(e) Keshav started his job at the age of 23 years 7 months. Now, he is 52 years 2

months old. How long has he been in this job?

multiplication and Division of Units of Time

example 1: Multiply 4 hours 15 minutes 30 seconds by 4.

Solution: Step 1: Multiply 30 seconds by 4. h min s
2
30 seconds × 4 = 120 seconds 4 15 30

Convert 120 seconds into minutes and seconds. × 4
00
120 seconds = 2 × 60 seconds = 2 minutes
Carry 2 minutes to the minutes column and write 00 seconds in the

seconds column.
Step 2: Multiply 15 minutes by 4 and add the carry over 2 minutes to the

product. h min s

15 minutes × 4 + 2 minutes = 62 minutes. 1 2
4 15 30
Convert 62 minutes into hours and minutes. × 4

62 minutes = 1 hour and 2 minutes 02 00
Carry 1 hour to the hours column and write 2 minutes in the minutes

column as a 2-digit number.

Step 3: Multiply 4 hours by 4 and add the carry over 1 hour to the product.
(4 × 4) hours + 1 hour = 17 hours.
h min s
Write 17 hours in the hours column. 1 2
4 15 30
Thus, the required product is 17 h 02 min 00s. × 4
17 02 00
example 2: Divide 16 hours 32 minutes 40 seconds by 5.

Solution: Step 1: Divide 16 hours by 5. 3 hours
Write 3 hours as quotient and 1 hour as 5 16 hours

remainder. 15 hour
1
Step 2: Convert the remainder 1
hour into minutes and add
32 minutes into it.

60 minutes + 32 minutes =
92 minutes

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