Ask questions, share knowledge, and connect with a vibrant community on IDNLearn.com. Discover detailed answers to your questions with our extensive database of expert knowledge.

7. It typically takes Mr. Dunn 20 minutes to get to school, but today it took him [tex]$40\%$[/tex] longer. How long did it take Mr. Dunn to get to school today?

a. 8 minutes
b. 12 minutes
c. 28 minutes
d. 60 minutes

\begin{tabular}{|l|l|l|}
\hline
Original & & \\
\hline
Part & & \\
\hline
New & & \\
\hline
\end{tabular}


Sagot :

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.