The price (p) of a commodity is first increased by k%, then decreased by k%; again increased by k%, and again decreased by k%. If the new price is q, then what is the relation between p and q?
EXPLANATION
Correct Option (4)
Let the initial price of the commodity be p.
After the first increase by k%, the price becomes:
After the first decrease by k%, the price becomes:
After the second increase by k%, the price becomes:
After the second decrease by k%, the final price q becomes:
This expression can be simplified using the algebraic identity .