Question

Comparing Scenarios
Math: Jenna had 80 math assignments this semester. After 6 weeks, she had 56 assignments left to do. Science: A graph has time (weeks) on the x-axis, and assignments on the y-axis. A line goes through points (3, 55) and (6, 40).

What can Jenna conclude about her math and science assignments?
She had more math assignments to start with and completed more math assignments weekly.
She had more math assignments to start with, but completed more science assignments weekly.
She had more science assignments to start with and completed more science assignments weekly.
She had more science assignments to start with, but completed more math assignments weekly.

Answer 1

Math: start 80, after 6 weeks 56 ⇒ completed 80−56 = 24 in 6 weeks ⇒ 24/6 = 4 per week.

Science: slope = (40−55)/(6−3) = −15/3 = −5, so science assignments decrease 5 per week and initial value y(0)=−5·0+70 = 70.

Conclusion: Jenna started with more math assignments (80 vs 70) but completed more science assignments each week (5 vs 4).