Page 187 - New Medley 5 Semester 1

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Example 11: Find of a dozen.
4

1 1 × 12 12
Solution: × 12 = = = 3 ( 1 dozen = 12 items)
4 4 4

1
Example 12: A car runs 10 km with 1 litre of petrol. How much
2

2
distance will it cover using 2 litres of petrol?
3

1
Solution:  With 1 L of petrol, the car runs 10 km.
2
2 1 2
∴ With 2 L of petrol, the car runs = 10 × 2
3 2 3
7 4
21 8
= × = 7 × 4 = 28 km
2 3

EXERCISE 4.4

A. Multiply.

2 3 7 5
1. 6 by 2. 12 by 3. 20 by 4. 36 by
3 4 10 12

2 4 7 5
5. by 10 6. by 14 7. by 10 8. by 16
5 7 15 8

B. Find the product of each of the following.

8 77 60 13 4 45 3 35
1. × 2. × 3. × 4. ×
11 112 91 15 9 56 7 48

2 9 3 12 18 5 6 65
5. × 6. × 7. × 8. ×
3 16 4 15 35 27 13 84

C. Multiply and express the result in the simplest term.
2 18 2 5 2 1 1 1
1. 4 × 2. 2 × 4 3. 8 × 7 4. 1 × 8
3 35 3 16 5 7 11 4
1 1 1 8 1
5. 2 × 9 6. 1 × 28 7. 15 × 3 8. × 1
3 7 5 15 2

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