A man buys two pens at ₹ 20 each. He sells one at a gain of 5% and other at a loss of 5%. Find his gain or loss per cent.(7th class math)

A man buys two pens at ₹ 20 each. He sells one at a gain of 5% and other at a loss of 5%. Find his gain or loss per cent.(7th class math).

Solution:Given One pens Rs. = 20

                          Tow pens Rs.= 40 = C P

According to question

Sell one at a gain of 5%.

then Selling price(S P) = (One pen) C P X (100 + Gain%)/100

                                     = 20 X (100 + 5)/100

                                     = 20 X 105/100

                                     = 21 Rs.

And other at a loss of 5%.

then Selling price(S P) = (one pen) C P X (100 - Loss%)/100

                                     = 20 X (100 - 5)/100

                                     = 20 X 95/100

                                     = 19 Rs.

Total Selling Price (S P) = One at a gain of 5% + other at a loss of 5%

                                       = (21 + 19) Rs.

                                       = 40 Rs.

Therefore S P = C P, then there is No Profit No Loss.