To solve this problem, we need to determine the time it took Mr. Dunn to get to school today after experiencing a 40% increase from his usual commuting time.
Let's break down the steps clearly:
1. Identify the original time:
- According to the problem, it typically takes Mr. Dunn 20 minutes to get to school.
2. Calculate the increase in time:
- The increase is [tex]\(40\%\)[/tex] of his usual 20 minutes.
3. Convert the percentage to a decimal:
- [tex]\(40\%\)[/tex] as a decimal is [tex]\(0.40\)[/tex].
4. Multiply the original time by the percentage to find the additional time:
- Additional time = [tex]\(20 \, \text{minutes} \times 0.40\)[/tex].
- Calculating this, we find that the additional time is [tex]\(8\)[/tex] minutes.
5. Calculate the new total time:
- Add the additional time to the original time to find the total time it took Mr. Dunn today.
- Total time = [tex]\(20 \, \text{minutes} + 8 \, \text{minutes}\)[/tex].
- This results in [tex]\(28\)[/tex] minutes.
So, the total time it took Mr. Dunn to get to school today is [tex]\(28\)[/tex] minutes.
Let's fill in the table provided:
\begin{tabular}{|l|l|l|}
\hline
Original & 20 minutes & \\
\hline
Part & 8 minutes & \\
\hline
New & 28 minutes & \\
\hline
\end{tabular}
Therefore, the correct answer is:
c. 28 minutes.
