Question

A coach shows the following ratio table to a team. The table shows the average amount of calories burned for a certain number of minutes of running.

Practice
Minutes of running
Calories burned
4
20
8
40
?
100

Based on the table, how many minutes does a person need to run to burn 100 calories?
12
20
28
68

Answer 1

To find out how many minutes a person needs to run to burn 100 calories based on the given ratio table, we first determine the pattern of calories burned per minute.

From the table:

- For 4 minutes of running, 20 calories are burned.
- For 8 minutes of running, 40 calories are burned.

We can see that when the minutes double from 4 to 8 (4 minutes → 8 minutes), the calories burned also double from 20 to 40.

This suggests there is a consistent ratio of calories burned per minute.

To find the rate:
- From 4 minutes to 8 minutes, the calories burned doubles:
- In 4 minutes: 20 calories / 4 minutes = 5 calories per minute.

Using this rate, we can calculate how many minutes are needed to burn 100 calories:

\[
\text{Calories burned per minute} = 5
\]
\[
\text{Minutes required to burn 100 calories} = \frac{100 \text{ calories}}{5 \text{ calories/minute}} = 20 \text{ minutes}
\]

Therefore, it takes **20 minutes** to burn 100 calories.

The answer is **20**.