Alvin owns coconut trees that yield 5 coconuts each. If a coconut can be sold for $3 and Alvin needs $90, how many coconut trees does he have to harvest?
Alvin needs to harvest 90/3= <<90/3=30>>30 coconuts to earn $90.
Therefore, the total number of trees that he has to harvest is 30/5= <<30/5=6>>6.
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