Page 200 - MathGPT_V1.0_C5

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\\November 3, 2023 12:46 PM Surender Prajapati Proof 5 Reader _________________________ Date: ___________________74

(b) 8 minutes 52 seconds = 8 minutes + 52 seconds

= (8 × 60) seconds + 52 seconds
= 480 seconds + 52 seconds = 532 seconds

(c) 2 hours 23 minutes 19 seconds

= 2 hours + 23 minutes + 19 seconds

= (2 × 60) minutes + 23 minutes + 19 seconds

= (120 minutes + 23 minutes) + 19 seconds
= 143 minutes + 19 seconds = (143 × 60) seconds + 19 seconds

= 8580 seconds + 19 seconds = 8599 seconds

Example 2: Convert the following:
(a) 10 hours into minutes (b) 8 hours 42 minutes into minutes

(c) 3 days 11 hours 30 minutes into minutes

Solution:

(a) Since, 1 hour = 60 minutes
So, 10 hours = (10 × 60) minutes = 600 minutes

(b) 8 hours 42 minutes = 8 hours + 42 minutes

= (8 × 60) minutes + 42 minutes

= 480 minutes + 42 minutes = 522 minutes

(c) 3 days 11 hours 30 minutes

= 3 days + 11 hours + 30 minutes
= (3 × 24) hours + 11 hours + 30 minutes ( 1 day = 24 hours)

= (72 hours + 11 hours) + 30 minutes

= 83 hours + 30 minutes

= (83 × 60) minutes + 30 minutes ( 1 hour = 60 minutes)

= 4980 minutes + 30 minutes
= 5010 minutes

Example 3: Convert the following:

(a) 7 days into hours (b) 5 days 18 hours into hours
Solution:

(a) Since, 1 day = 24 hours

So, 7 days = (7 × 24) hours = 168 hours

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