Total cost price of two watches is Rs.8000 and selling price of each is equal. 1st is sold at 22% loss and 2nd is sold at 17% profit. Find the cost price of watch which is sold at 15% loss.

Rs.4800/-

             C.P.            :         S.P.

1st :         50            :          39        ........(i)

2nd:         100          :         117

ATQ, (S.P. is same), therefore multiple (i) by 3

                C.P.            :         S.P.

1st :         150            :          117      

2nd:         100            :          117

               250 (total C.P.)

⇒ 250R = 8000 (given)

⇒ 1R    = 32

Hence,

C.P. of 1st article = 150R = 150 × 32 = Rs.4800/-