By selling Toffees at 20 for a rupee, a man loses 40 %. To gain 20 %, for one rupee he must sell?

A. 16 toffees
B. 20 toffees
C. 25 toffees
D. 24 toffees
Explanation:
He sells 20 toffees
S.P = Rs. 1 and loss = 4%
C.P = (11/96 × 1) = Rs. 25/24
Gain = 20%
S.P = Rs. (120/100 × 25/24) = Rs. 5/4
Rs. 5/4 toffees sold = 20
Rs. 1 toffees sold = (20 × 4/5) = 16