Q1 of 8 Page 54

Raju bought seven notebooks of two hundred pages and five of hundred pages, for 107 rupees. Joseph bought five notebooks of two hundred pages and seven of hundred pages, for 97 rupees. What is the price of each kind of notebook?

Let the price of two hundred pages notebook be ‘x’ and price of hundred pages book be ‘y’.


According to the question,


Raju bought 7 notebooks of two hundred pages and five of hundred pages for 107 rupees


⇒ 7x + 5y = 107 ... (1)


Joseph bought five notebooks of two hundred pages and seven of hundred pages, for 97 rupees


⇒ 5x + 7y = 97… (2)


Equating (1) and (2)


7x + 5y = 107


5x + 7y = 97


Multiply Equation (1) by 7 and equation (2) by 5


Then, Subtract equation (2) from (1)




x = 11


Put x = 11 in Equation (3)


49 × 11 + 35 y = 749


⇒ 539 + 35y = 749


⇒ 35y = 749 – 539


⇒ 35y = 210


⇒


⇒ y = 6


Hence, price of two hundred pages notebook is 11rupees and price of hundred pages notebook is 6 rupees.


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