Question

A grocer mixed two varieties of coffee seeds, the cost prices of which are $12.50$ and Rs. $8$ per kg. respectively. He gains $20\%$ by selling a kg. of the mixture at Rs. $12$/-. The proportion in which he has mixed the two varieties is

• A. $2:3$
• B. $3:4$
• C. $4:5$
• D. $4:3$

Answer 1

The correct option is C $4:5$

cost of coffee seeds A = 12.50 Rs per kg

cost of coffee seeds B = 8 Rs per kg

The mixture of A & B = 12 Rs per kg

$C.P=\frac{S.P\times 100}{Gain}$

Gain = 20%

$=\frac{12\times 100}{120}=10$

$12.5x+8y=10(x+y)$

$12.5x-10x=10y-8y$

$2.5x=2y$

$x:y=2:2.5\simeq 2:3$