Answer:
2597
Step-by-step explanation:
For the cost to be the same:
18648+23.5b=83556+10b subtract 10b from both sides
18648+13.5b=83556 subtract 18648 from both sides
13.5b=64908 divide both sides by 13.5
b=4808
So if 4808 books are produced the cost of both methods is the same.
3rd angle is 100
All Angles of a triangle add together will equal 180
20+60=80
180-80=100
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