Page 150 - SK Year 5 Mathematics DLP

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1
1.5 hours 0.75 hour 4 hour

a Calculate the total duration needed to help mother in the kitchen
and to help father wash his car.

1.5 hours + 0.75 hour = hours
1
1 .50 hours
+ 0. 7 5 hour
2.25 hours

1.5 hours + 0.75 hour = 2.25 hours
The total duration of these two activities is 2.25 hours.

b What is the duration, in minutes, to help father wash his car and
water the plants?
1
0.75 hour + hour = minutes
4

0.75 hour 1 1 15 1
45 minutes
= (0.75 × 60) minutes 4 hour = ( × 60) minutes + 1 5 minutes
4
= 45 minutes 1
= 15 minutes 60 minutes
4 3
0. 7 5
× 60
0 4 5. 00

1
0.75 hour + hour = 60 minutes
4
The duration of both activities is 60 minutes.

1
Convert hour to 0.25 hour. Then, add 0.75 hour. Is your answer the
4
same as the answer above? Discuss.

142 4.3.1 (i) • Emphasise that adding time in decimals is the same as adding
4.3.2 (i) whole numbers. Decimal points must be aligned in the same
column.