Jacob had math homework on 81 evenings.
Step-by-step explanation:
Time spent of each evening = 1/3 of an hour
Time spent in minutes = 
Total time spent = 27 hours
Total time spent in minutes = 27*60 = 1620 minutes
Let,
x be the number of evenings spent doing math homework.
Time spent each day* Number of evenings = Total time spent

Dividing both sides by 20

Jacob had math homework on 81 evenings.
Keywords: multiplication, division
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