The average pocket money of 3 friend A, B, C is Rs. 80 in a particular month. If B spends double and C spends triple of what A spends during that month and if the average of their unspent pocket money is Rs. 60, then A spends (in Rs.)-

A. Rs. 10

B. Rs. 20

C. Rs. 30

D. Rs. 40

Answer: Option A

Solution(By Examveda Team)

According to the question,
Pocket money
$$\eqalign{ & \Rightarrow \frac{{A + B + C}}{3} = 80 \cr & \Rightarrow A + B + C = 240 \cr} $$
Unspent pocket money
$$\eqalign{ & \Rightarrow \frac{{A + B + C}}{3} = 60 \cr & \Rightarrow A + B + C = 180 \cr} $$
Spent pocket money = 240 - 180 = Rs. 60
Given:
$$\frac{B}{A} = \frac{2}{1}\,\,{\text{and}}\,\,\frac{C}{A} = \frac{3}{1}$$

	A	B	C
Spent	1	2	3	= 6 units

6 units -------- 60
1 unit --------- 10
∴ A spent = 1 × 10 = Rs. 10