Question

Beck finished 30% of his homework in 12 minutes. How many minutes will it take him to complete all of his homework?

Part A
Let m = the number of minutes it will take Beck to finish his homework.
Choose the equation that can be used to find the solution to the problem.
A. 0.03m = 12
B. 12m = 0.3
C. m = 0.3 × 12
D. 0.3m = 12
Part B
Use the expression from Part A to find the total number of minutes it will take Beck to complete all of his homework.
Enter your answer in the box.
__________ minutes

Answer 1

Part A) The answer is D) 0.3m = 12.
Part B) The answer is 40 minutes.

If m is the total number of minutes it takes him to complete his homework, 30% of m is given by 0.3m. Since 30% was done in 12 minutes, we have 0.3m=12.

To solve this, we divide both sides by 0.3:
0.3m/0.3 = 12/0.3
m = 40

Answer 2

The correct answer is choice D. If you put choice D into words, it is saying 30% (0.3) of the total is 12 minutes.

To solve this, use inverse operations.

0.3m = 12
0.3 0.3
m = 40

It will take Beck 40 minutes.