Question

the cost price of 10 pens is the selling price of 8 pens find the gain or loss percent

Answer 1

cp of 10pens =sp of 8 pens
then
cp =8
sp=10
profit=sp-cp
=10-8
=2
profit% =profit/cp × 100
= 2/8 ×100
=1/4 ×100
=25% gain