Respuesta :

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.

Earning in 2.5 years = $7500

1 year = 12 months  

2.5 years = 2.5 ⋅ 12 = 30 months    

Then, earning in 30 months = $7500

Therefore, earning in 1 month = 7500/30 = $250

The unit rate of his earning per month is $250.