Question

By selling 100 pencils, a shopkeeper gains 30%
profit. The cost price of 20 pencils is Rs. 80. What is
the gain

Answer 1

25%

S.P. of 100 pencils − C.P. of 100 pencils = S.P. of 20 pencils

⇒ S.P. of 80 pencils = C.P. of 100 pencils  

Let C.P. of 1 pencil = Rs. 1

Then S.P. of 80 pencils = Rs. 100  

⇒ C.P. of 80 pencils = Rs. 80

∴ Profit % =  

80

100−80

​

×100=  

80

20

​

×100=25%