Question

Jill estimated a room to be 18ft tall. It was actually only 15 ft tall. What is her percentage of error? (tenth)

Answer 1

To calculate Jill's percentage of error, we can use the formula for percentage error:

\[
\text{Percentage of Error} = \left( \frac{|\text{Estimated Value} - \text{Actual Value}|}{\text{Actual Value}} \right) \times 100
\]

In this case:

- Estimated Value = 18 ft
- Actual Value = 15 ft

Now, substituting the values into the formula:

\[
\text{Percentage of Error} = \left( \frac{|18 - 15|}{15} \right) \times 100
\]

\[
= \left( \frac{3}{15} \right) \times 100
\]

\[
= 0.2 \times 100
\]

\[
= 20\%
\]

Therefore, Jill's percentage of error is **20.0%**.