Question

boy sells 2 wristwatches for rs 1200rs on one he gains 20% and on other for 20% loss find CP and total gain or loss %

Answer 1

let cp be x
=> sp= (1+20/100) (1-20/100) x
=> 1200 = 6/5 * 4/5 * x
=> x = 1200 * 25 / 24
=> x = 1250

loss = 1250 - 1200
       = 50

loss % = 50 / 1250 * 100
           =  4 %