Question

Cost of 6 books and 8 notebooks is 460 rupee and that of 4 books and 5 note books is 300 rupee. Product of costs of 1 book and 1 note book will be

Answer 1

let cost of books =x rs

let cost of notebooks =y rs

A.T.Q.

6x+8y=460

(6x+8y=460) ÷ 2

3x +4y = 230 (1)

4x+5y = 300 (2)

multiply by 4 in eq (1) and 3 in eq (2) sub. them

12x+16y =920

12x+15y =900

- - -

y =20 rs

put value in eq (1)

3x +4(20) = 230

3x =230-80

3x= 150

x = 50 rs