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Mathematics>Standard Multiple Choice

Read the following SAT test question and then click on a button to select your answer.

During his busiest week as an origami artist, Nate made 20 origami figures per hour on weekdays and 30 per hour on the weekend. During this particular week, Nate made a total of 650 origami figures by working 5 times as many hours on weekdays as he did on the weekend. If he worked x hours on the weekdays and y hours on the weekend, how many total hours did he work during this week?

A.5

B.20

C.25

D.30

The correct answer is D

Explanation

If Nate worked 5 times as many hours on weekdays than on weekends, the first equation in the system is x=5y. If Nate made 20 origami figures per hour during weekdays, and 30 origami figures per hour during the weekend, and 650 origami figures the second equation in the system is 20x+30y=650.

Next, substitute 5 y for x in the second equation and solve for y to find that the total number of hours Nate worked on the weekend was 5. Then, substitute 5 for y in the first equation and solve for x to find that the total number of hours Nate worked on weekdays was 25. Lastly, find the total number of hours Nate worked during the week by finding x+y=30; that is, Nate worked 30 hours total.