Question:
Two successive price increase of 10% and 10% of an article are equivalent to a single price increase of:

Option A):
33(1/3)
Option B):
21%
Option C):
26(2/3)
Option D):
25%

Correct Answer is Option B):
21%

Explanation:
100----10%↑--→110---10%↑--→121.
Equivalent price increase = 21%.