Okay this is how I would figure this out:
I would take 9 divided by 3 and get 3, so he can tile abut 3 square ft. in 15 minutes.
Then, I would multiply 3 by 4 because there are 4 15 in an hour. I would get 12.
So it takes Jakob 1 hour to tile 12 square feet.
Your answer is: He can tile about 12 square feet per hour.
Hope this helped :)
2.5 years = 30 months
7500$ in 30 months
x$ in 1 month
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x = (7500*1)/30 = 250
The answer is 250$/month.
Answer: The answer would be f^-1 (x) = x/2 - 3/2
