What is the rate of change in the profit for this time period?

Since the beach club made $39,100 in May and $59,200 in August (That's a lot of money) That means that it grew per month.
We subtract $59,200 by $39,100 which would give you an equal of $20,100
Meaning that they made $21,100 between those months.
So, there is May, June, July, August.
So, since May up to August, they made $20,100, so we divide those $20,100 by 3 since there are three more months after May.
So, each months, the profit goes up by $6,700.
So, in June, they made $45,800
On July, they made $52,500
On August, they made $59,200 and so on.
So, the rate is +$6,700 per month.
I hope this helps.
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