Answer: $1.73
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Step-by-step explanation:
The simple interest formula is
i = P*r*t
that calculates the interest only
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Let's calculate how much interest Lin will pay back if she goes with the 7 year loan at 4.5% simple interest rate.
i = P*r*t
i = 575*0.045*7
i = 181.125
i = 181.13
Repeat for the other loan (8 years, 3.9% simple interest)
i = P*r*t
i = 575*0.039*8
i = 179.40
Subtract the results
181.13 - 179.40 = 1.73
She saves $1.73 if she goes with the second loan.