When Destiny agreed to proofread her brother's essay, she expected that it would be 2 pages long. When he gave her the essay, it was actually 4.5 pages long. What is the percent error for her estimate?

To calculate the percent error in Destiny's estimate, you can use the formula for percent error:

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

In this case, the estimated value is 2 pages and the actual value is 4.5 pages.

Now we can plug in the values into the formula:

\[ \text{Percent Error} = \left( \frac{4.5 - 2}{2} \right) \times 100 \]

\[ = \left( \frac{2.5}{2} \right) \times 100 \]

\[ = 1.25 \times 100 \]

\[ = 125% \]

Thus, the percent error in Destiny's estimate is 125%.