Question

If the cpi was 207 in 2009 and 225 in​ 2013, what wage would someone who earned a​ $50,000 income in 2009 have to earn in 2013 in order to keep her purchasing power​ constant?

Answer 1

Given:
CPI income
2009 207 50,000
2013 225 ?

50,000 / 207 = 241.55 purchasing power.

241.55 * 225 = 54,348.75

She should earn at least 54,348.75 in 2013 in order to keep her purchasing power constant.