Question

if the cpi is 120 in 1996 and 180 in 2002, then between 1996 and 2002, prices have increased by
180%.
80%.
60%.
50%.

Explanation:

Step1: Recall the formula for percentage increase

The formula for percentage increase is $\text{Percentage Increase} = \frac{\text{New Value} - \text{Old Value}}{\text{Old Value}} \times 100\%$.

Step2: Identify the old and new values

Here, the old value (CPI in 1996) is 120 and the new value (CPI in 2002) is 180.

Step3: Substitute the values into the formula

First, calculate the difference: $180 - 120 = 60$. Then, divide by the old value: $\frac{60}{120} = 0.5$. Multiply by 100% to get the percentage: $0.5\times100\% = 50\%$.

Answer:

50% (the option with "50%")