If you have 10 boxes and you shade 3 of these boxes, then the fraction of shaded boxes is 3/10. The fraction of unshaded boxes would just be the remainder of boxes, or 7/10.
Answer:
36 minutes
Step-by-step explanation:
The key is to get the same amount of time for each.
9 * 12 = 108
At 12 minutes per job,
in 108 minutes Alyssa could do
108/12 = 9 jobs
At 9 minutes per job,
Together in 108 minutes they could do
108/9 = 12 jobs
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In 108 minutes Mirada does
12 - 9 = 3 jobs
108/3 = 36 minutes per job
All except for the third option are correct
