On selling 13 balls at Rs. 720, there is a loss equal to the cost price of 5 balls. The cost price of a ball is: Select
A) s. 45 B) s. 50 C) s. 55 D) s. 60 E) s. 90
(C.P. of 13 balls) - (S.P. of 13 balls) = (C.P. of 5 balls)   C.P. of 8 balls = S.P. of 13 balls = Rs.720.   C.P. of 1 ball = Rs.720/8	= Rs.90.   Answer: Option s. 90
<result>E</result>
On selling 13 balls at Rs. 720, there is a loss equal to the cost price of 5 balls. The cost price of a ball is: