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3 years ago

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Raju bought seven notebooks of two hundred pages and five of hundred pages, for 107 rupees. Joseph bought five notebooks of two

hundred ages and seven of hundred pages, for 97 rupees. What is the price of each kind of notebook?

1 answer:

olga nikolaevna [1]3 years ago

8 0

Answer:

Large books = 11

Small books = 6

Step-by-step explanation:

7x + 5y = 107

7x = 107 - 5y

x = 107/7 - 5y/7

5x + 7y = 97

5 (107/7 - 5y/7) + 7y = 97

535/7 - 25y/7 + 7y = 97

535/7 + 24y/7 = 97

535 + 24y = 679

24y = 679 - 535

y = 144/24 = 6: So x =

7x + 5(6) = 107

7x = 107-30

x = 77-7 = 11

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