Mr. and Mrs. Bailey need to invest $2906.50 so as to send their son to college.
Compound interest is given by:
[tex]A=P(1+\frac{r}{n})^{nt}[/tex]
where A is the amount after t years, P is initial amount, r is the rate and n is the times compounded per period
Given that n = 1, r = 9% = 0.09, A = $7500 t = 11. Hence:
[tex]7500=P(1+\frac{0.09}{1} )^{1*11}\\\\P=\$2906.50[/tex]
Mr. and Mrs. Bailey need to invest $2906.50 so as to send their son to college.
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