Question

Which expression could be used to solve this problem?

Bart practices piano every day. First he practices songs for 20 minutes. Then he practices scales for 15 minutes. How much time does Bart practice piano in 3 days?


A.
3 × (20 – 15)

B.
20 × (15 + 3)

C.
3 × (20 + 15)

D.
20 × (15 – 3)

Answer 1

C. 3 x (20 + 15)

Explanation:

You have to add 20 + 15 to get 45 so the 20 + 15 goes in the (). It says how much time he has practiced in 3 days so you have to multiply the things in the () by 3 so the 3 goes out side the ().

Answer 2

C. 3 × (20 + 15)

Explanation:

If Ben practices this way every day, then the amount of time should be the same.

20 minutes of song practice, 15 minutes of scale practice.

20+15=35

multiply the 35 minutes per day by three

35 times 3 equals 105

So the answer is C.

3 × (20 + 15)

3(35)=105