Dean ran 5 miles this week and wants to know how many kilometers he ran. His work is below:

Question

5 miles / 1 x 1.61 km / 1 mile = 80.5 miles

Units of Length:
Customary System Units - Metric System Units
1 mile - 1.61 kilometers

What are Dean's errors? Select the two that apply.

• Dean should have kilometers in the denominator of the conversion factor.
• Dean should have used two conversion factors.
• The decimal point in his answer is in the wrong place.
• He has the wrong units in his answer.

Answer 1

Dean's errors are:

1. Dean should have kilometers in the denominator of the conversion factor. - Dean's conversion factor incorrectly places kilometers in the numerator instead of the denominator, making the conversion incorrect.

2. He has the wrong units in his answer. - Dean's final answer states "80.5 miles," which is incorrect since he should be calculating the distance in kilometers, not miles.

The correct conversion process would involve using the conversion factor correctly set up to cancel out miles, leading to a result in kilometers.

Combining these two points highlights the key errors in Dean's work.