A grocer has a sale of Rs. 2500, Rs. 4000, Rs. 3540 for 3 consecutive months. How much sale must he have in the fourth month so that he gets an average sale of Rs. 2890?
Choose the correct choice from the following:	A) rs . 3500	B) rs . 1520	C) rs . 4996	D) rs . 4000	E) rs . 900

Rationale: total sale for 5 months = rs . ( 2500 + 4000 + 3540 ) = rs . 10040 . required sale = rs . [ ( 2890 x 4 ) - 10040 ] = rs . ( 11560 - 10040 ) = rs . 1520 . b )
Answer: B