Let x=# of trees (which in this case would produce 34 lbs of coffee)
We have the following ratio:
# of Trees # of Trees
---------------- = -----------------
# of lbs of coffee # of lbs of coffee
Which algebraically looks like
Start with the given ratio
Multiply both sides by 34
Multiply
Simplify
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Answer:
So the answer is which means that 28 trees are needed to produce 34 lbs of coffee.