Answer:

Explanation:
You need to analize the information provided.
The amount of money the student saves in 1 week is: $20
You need to calculate the amount of money the student will have saved in 21 weeks.
Therefore, in order to solve the exercise, you need to multiply the amount of money the student saves in 1 week by 21. The product obtained will be the amount of money the student will have saved in 21 weeks.
Then, you get:
