Question

a man bought bananas at the rate of Rs 15 per dozen and sold them at the rate of 10 for Rs 15. Find his gain or loss percent

Answer 1

1 DOZEN=12 bananas
so he brought 12 bananas for ₹15
so CP of 1 banana=₹15÷12

he sold 10 bananas at the rate of ₹15
so the SP of 1 banana=₹15÷10
as sp is greater than cp there will be a profit

profit=₹15÷10-₹15÷12=30÷120=₹3÷12
profit%=3/12÷15/12. ×100=20%

Answer 2

Cost per 12 is Rs 15

Cost per 1 is Rs 15/12

SP per 1 is Rs 15/10

Profit = SP - CP

==> 15/10 - 15/12

==> 3/2 - 5/4

==> (6-5)/4

==> 1/4

Profit%

==> Profit/CP *100

==> 1/4 / 15/12* 100

==> 1/4 * 12/15* 100

==> 1/5 *100

==>20%

The profit is 20%

Hope it helps

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