Page 138 - Maths Class 05

2. Convert the following.

a. 360 minutes = hours minutes b. 232 minutes = hours minutes

c. 400 minutes = hours minutes d. 720 minutes = hours minutes

e. 210 minutes = hours minutes f. 330 minutes = hours minutes
3. Add the following.

a. 40 minutes 9 seconds and 36 seconds

b. 3 hours 30 seconds and 3 hours 45 seconds
c. 8 hours 12 minutes and 6 hours 15 minutes
d. 5 minutes 35 seconds and 3 minutes 25 seconds

4. Add columnwise.

a. 3 hour 42 minutes 29 seconds and 4 hours 40 minutes 40 seconds
b. 12 hours 45 minutes 50 seconds and 4 hours 17 minutes 30 seconds

c. 15 hours 37 minutes 21 seconds and 2 hours 35 minutes 20 seconds
d. 5 hours 21 minutes 40 seconds and 21 hours 43 minutes 15 seconds

e. 10 hours 40 minutes and 3 hours 10 minutes
f. 20 hours 36 minutes 43 seconds and 15 hours 37 minutes 34 seconds

Word Problems on Addition

Example : Anil took 21 minutes to climb stairs of his home. How many seconds did
he take ?

Solution : Time taken by Anil to climb stairs = 21 minutes

We know that,
1 minute = 60 seconds

21 minutes = 21 × 60 = 1260 seconds
So, Anil took 1260 seconds to climb stairs of his home.

Example : Sam leaves for school at 6:35 a.m. It takes him 1 hr 45 min to reach the
school. At what time will he reach the school ?

Solution : Sam leaves for school at = 6:35 a.m.

Time taken to reach the school = 1 hr 45 min.
He reached the school at hr min

= 6 h + 35 min + 1 h 45 min 6 35
= 7 h 80 min + 1 45

= 7 h + 1 h 20 min 7 80

= 8 hr 20 min
Therefore, Sam will reach the school at 8:20 a.m.

Mathematics-5 138