The ratio of cost price and selling price of an article is 20 : 21. What is the gain per cent on it?
Let × be the common multiple
CP = 20x
SP = 21x
Gain = SP – CP
= 21 × – 20x
= x
Gain Percent = 
= 5%
14
The ratio of cost price and selling price of an article is 20 : 21. What is the gain per cent on it?
Let × be the common multiple
CP = 20x
SP = 21x
Gain = SP – CP
= 21 × – 20x
= x
Gain Percent =
= 5%