Page 167 - ICSE Math 4

Example 13: Ananya’s music class starts at 5:45 p.m. and gets over at 7:15 p.m. Find the
dura on of Ananya’s music class.
Solu on: Time at which Ananya’s music class starts = 5:45 p.m. = 17 h 45 min

Time at which Ananya’s music class ends = 7:15 p.m. = 19 h 15 min

Dura on of Ananya’s music class Calcula on

= Finishing me – Star ng me h min
18 75
= 19 h 15 min – 17 h 45 min (15 + 60 = 75, since
19 15 we have borrowed
= 1 h 30 min – 17 45 1 h from the original
hours)
So, the dura on of Ananya’s music class 1 30
is 1 h 30 min.

Exercise 12.5

1. Look at the given clocks and calculate the dura on of me passed between these
clocks using forward or backward coun ng.

(a) (b)

2. What will be the me a er 35 minutes for the following mings?
(a) 4:20 p.m. (b) 1:50 a.m. (c) 6:25 p.m.

(d) 12:25 p.m. (e) 12:40 a.m. (f) 3:15 p.m.

3. Calculate the dura on in minutes between the given mings.

(a) 9:45 a.m. and 9:55 a.m. (b) 7:35 p.m. and 7:50 p.m.
(c) 3:30 p.m. and 4:00 p.m. (d) 8:20 a.m. and 9:00 a.m.

(e) 12 noon and 12:05 p.m. (f) 4:20 p.m. and 5:05 p.m.

4. Calculate the dura on in hours and minutes between the given mings.
(a) 6:50 p.m. and 7:30 p.m. (b) 8:50 a.m. and 11:20 a.m.

(c) Quarter past 2 and half past 3 (d) Quarter to 4 and half past 5

(e) Quarter past 5 and quarter to 7 (f) 3:20 p.m. and 6:45 p.m.

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