The economy's inflation rate in 2010, with the base year as 2010, was 20%. The Option D is correct..
Inflation Rate = [(CPI in Current Year - CPI in Base Year) / CPI in Base Year] * 100
CPI in 2010 = [(2 * $45) + (15 * $4)] / [(2 * $40) + (15 * $3)]
= ($90 + $60) / ($80 + $45)
= $150 / $125
= 1.2
CPI in 2009 = [(2 * $40) + (15 * $3)] / [(2 * $40) + (15 * $3)]
= ($80 + $45) / ($80 + $45)
= $125 / $125
= 1.0
Inflation Rate= {(CPI 2010 - CPI 2010)/CPI 2010} * 100
= [(1.2 - 1.0) / 1.0] * 100
= [(0.2 / 1.0) * 100
= 20%
Note: The organized question is attached below.