Question

By selling an article at 270 a man loses 10%. How much would he gain if he selled it at 360?

Answer 1

Given,
SP=Rs 270, loss=10%
Solving it in Unitary Method we get,

If CP is Rs100, then SP is Rs90,
If SP is Rs90, then CP is Rs100,
If SP is Re1, then CP is Rs$\frac{100}{90}$,
If SP is Rs270, then CP is Rs$\frac{100}{90}$×270

By cancelling the terms,
 we get then CP as Rs 300,

Now, CP=Rs 300, SP=Rs 360
Gain= Rs(360-300)= Rs 60

Gain%= ($\frac{Profit}{CP}$×100)%
          =($\frac{60}{300}$×100)%
          =20%

Answer 2

Let C.P. be x
                   Therefore, Loss = (10% of x)
                                           =(x÷10)
                  Therefore,S.P. = C.P.- Loss
                                       =x-(x÷10)
                                       =9x÷10
By the Problem,
                     270 =9x÷10
                  ⇒9x=270×10
                  ⇒x=2700÷9
                  ⇒x=300
Therefore, C.P. = 300

If the man sold it at 360,
                           Amount he would gain = His Profit
                                                            =360-300
                                                            = 60
                          His Gain% ={ (60÷300)×100}%
                                          = 20%