Question

A battery is charged. The percentage of the battery’s capacity that is charged as a function of time (in minutes) is graphed.

How many percentage are added every 6 minutes?
A- 12 percent
B- 6 percent
C- 10 percent
D- 2 percent

Answer 1

12%

Explanation:

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Answer 2

A- 12 percent

Explanation:

You can see on the graph that the charged percentage of capacity changes from 40 to 50 in 5 minutes. Then the increase in 6 minutes will be slightly more than 10 percent.

The linear rate is (10%)/(5 min) = 2%/min, so in 6 minutes it will be

(2%/min)×(6 min) = 12%

This calculation is consistent with our observation from the graph.

Every 6 minutes, 12 percent is added to the capacity.