A number is decreased by 10% and then increased by 10%. The number so obtained is 10 less than the original number. What was the original number?

A 1000

B 1050

C 1500

D 2000

Correct Answer: Option A

here,

if 10% decreased, then ,number is =900 again,if increase 10 % number=990 (1000-990) =10 less from original number