To find Teresa's percent error, we can use the formula for percent error, which is given by:
In this case:
- Estimated Value = 18 feet
- Actual Value = 16 feet
Now, we can calculate the absolute error:
Now, plug the values into the percent error formula:
Calculating the fraction:
Now, multiply by 100 to convert it to a percentage:
So, Teresa's percent error is:
Thus, rounded to the nearest tenth, Teresa's percent error is 12.5%.