A fruit seller sold big, medium and small sizes apples of Rs. 15, Rs. 10 and Rs. 5, respectively. The total number of apples sold were in the ratio 3 : 2 : 5. Find the average cost of an apple.

A. 8

B. 10

C. 9

D. 7

Answer: Option C

Solution(By Examveda Team)

Let the no. of apples be 3x, 2x and 5x
∴ Average Cost
$$\eqalign{ & = \frac{{3x \times 15 + 2x \times 10 + 5x \times 5}}{{3x + 2x + 5x}} \cr & = \frac{{45x + 20x + 25x}}{{10x}} \cr & = \frac{{90x}}{{10x}} \cr & = {\text{Rs}}{\text{.}}\,{\text{9}} \cr} $$