A man buys 12 notebooks and 5 markers for Rs. 700. If he had bought 8 notebooks and 7 markers, he would have paid Rs. 160 less. What is the cost of 2 notebooks and a marker?

A man buys 12 notebooks and 5 markers for Rs. 700. If he had bought 8 notebooks and 7 markers, he would have paid Rs. 160 less. What is the cost of 2 notebooks and a marker? Correct Answer Rs. 120

Let the price of a notebook and a marker be Rs. ‘x’ and Rs. ‘y’ respectively

⇒ Price of 12 notebooks and 5 markers = 12x + 5y = 700        ----(1)

Also,

⇒ Price of 8 notebooks and 7 markers = 700 - 160 = 540

⇒ 8x + 7y = 540        ----(2)

Multiplying (1) by 2 and subtracting from 3 times of (2), we get

⇒ {3(8x + 7y)} - {2(12x + 5y)} = 3(540) - 2(700)

⇒ 24x + 21y - 24x - 10y = 1620 - 1400

⇒ 11y = 220

⇒ y = 220/11 = 20

Substituting in (1), we have

⇒ x = (700 - 100)/12 = 600/12 = Rs. 50