Question

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

Answer 1

To calculate Jill's percentage of error in her estimation, you can use the following formula:

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

In this case:
- Estimated Value = 18 ft
- Actual Value = 15 ft

First, calculate the difference between the estimated value and the actual value:

\[
\text{Difference} = 18 \, \text{ft} - 15 \, \text{ft} = 3 \, \text{ft}
\]

Now, plug the values into the formula:

\[
\text{Percentage of Error} = \left( \frac{3 \, \text{ft}}{15 \, \text{ft}} \right) \times 100
\]

Calculating this gives:

\[
\text{Percentage of Error} = \left( 0.2 \right) \times 100 = 20\%
\]

Thus, Jill's percentage of error is **20.0%** (to the nearest tenth).