Question 664310
$40 per hour
15 students per week
Each hourly student earns them $40 and there are 15 students, so this is multiplication.
40 * 15 = 600 per week
There are 4 weeks per month to earn 600 each week, this is again multiplication.
600 * 4 weeks = 2400 per month
Out of their earned 2400 they must pay for their overhead, the building rent
2400 - 400 = 2000 profit 
They are left with $2000 between them.
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