Page 85 - ICSE Math 6

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Example 29: Tia read of a book on the first day and of the remaining book on the second day.
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What fraction of the book did Tia read in two days? If 90 pages were left to be read,

then find the total number of pages in the book.
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Solution: After the first day, fraction of book left to be read = 1 – =
4 4

2 3 2 3 3
The fraction of book read on the second day = of = × =
5 4 5 4 10
1 3 1×5 3×2+ 11
\ The fraction of book Tia read in two days = + = =
4 10 20 20

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The fraction of book left to be read = 1− =
20 20 Maths Info
As, 90 pages were left to be read, therefore:
9 9 In fractions, the whole quantity
of total pages = 90 ⇒ × total pages = 90 may be considered as 1.
20 20
9 20 10 90 ×20
Total pages = 90 ÷ = 90 × = = 200
20 9 9 1
\ Total number of pages = 200

Example 30: Anny plants 5 saplings in a row in her garden. The distance between two adjacent
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saplings is m. Find the distance between the first and the last saplings.
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S1 S2 S3 S4 S5
Solution:
Let the saplings be planted at S1, S2, S3, S4 and S5.
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Distance between two adjacent saplings = m
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3 12 2
∴ Distance between S1 and S5 = 4 × = = 2 m
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Example 31: A bike covers 64 km using 1 litre of petrol. How much distance will it cover using
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3 litres of petrol?
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Solution: Distance bike covers using 1 litre of petrol = 64 km
1 1 13
∴ Distance bike will cover using 3 litres of petrol = 3 × 64 = × 64
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= 13 × 16 = 208 km
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Example 32: An airplane can cover 1,224 km in 1 hours. What distance can it cover in:
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(a) 1 hour (b) 2 hours
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Solution: (a) As, the airplane can cover 1,224 km in 1 hours, therefore:
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Distance it can cover in 1 hour = 1,224 ÷ 1 3
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