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Question
The weight of 65 books is 13 kg.
(i) What is the weight of 80 such books?
(ii) How many such books weigh 6.4 kg?
Solution
Weight of 65 books = 13 kg
(i) Weight of 1 book = `13/65` kg
Weight of 80 books = 80 × `13/65=1040/65` = 16 kg
(ii) Number of books weighing 13 kg = 65
Number of books weighing 1 kg = `65/13` = 5
Number of books weighing 6.4 kg = 6.4 × 5 = 32
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