How do you solve break even problems?

A break even problem is found when you calculate starting a buisieness
so lets ssay you have to buy 3 coppy machines and each machine costs 2000 dollars,
the people who want to use your coppy machines have to pay $0.40 per page
so you have spent 6000 dollars already
when you break even, it is when your earnings equals your expenditure (how much you earned equals how much you paid)

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