To calculate Teresa’s percent error in estimating the height of the giraffe, we can use the formula for percent error, which is given by:
\[ \text{Percent Error} = \left( \frac{|\text{Estimated Value} - \text{Actual Value}|}{\text{Actual Value}} \right) \times 100 \]
In this case, Teresa estimated the height of the giraffe to be 18 feet, while the actual height is 16 feet. First, we need to find the absolute difference between the estimated and actual values:
\[ |\text{Estimated Value} - \text{Actual Value}| = |18 - 16| = 2 \text{ feet} \]
Next, we divide this difference by the actual value (16 feet) to find the relative error:
\[ \frac{|\text{Estimated Value} - \text{Actual Value}|}{\text{Actual Value}} = \frac{2}{16} = 0.125 \]
Now, we multiply this result by 100 to convert it to a percentage:
\[ \text{Percent Error} = 0.125 \times 100 = 12.5% \]
Therefore, Teresa’s percent error in estimating the height of the giraffe is 12.5%. This means that her estimate was off by about 12.5% of the actual height.