Question

the selling price of 10 pencils is equal to the cost price of 11 pencils .What is the profit percentage?

Answer 1

sp of 10 pencils=cp of 11 pencil=x
so cp of one pencil=x/11
and sp of one pencil is =x/10
profit=sp-cp=x/10-x/11
                     =x/110
profit %=profit*100/cp
              =x*100*11/110*x=10%
so profit percentage=10%

Answer 2

sp of 10 pencils=cp of 11 pencil=x

so cp of one pencil=x/11

and sp of one pencil is =x/10

profit=sp-cp=x/10-x/11

                     =x/110

profit %=profit*100/cp

              =x*100*11/110*x=10%

so profit percentage=10%

Hope it's helps