Answer:
[tex]r=6.5\%[/tex] Â
Step-by-step explanation:
we know that  Â
The compound interest formula is equal to Â
[tex]A=P(1+\frac{r}{n})^{nt}[/tex] Â
where Â
A is the Final Investment Value Â
P is the Principal amount of money to be invested Â
r is the rate of interest  in decimal
t is Number of Time Periods Â
n is the number of times interest is compounded per year
in this problem we have Â
[tex]t=4\ years\\ P=\$8,000\\A=\$10,292.76\\r=?\\n=1[/tex] Â
substitute in the formula above
[tex]10,292.76=8,000(1+\frac{r}{1})^{1*4}[/tex] Â
solve for r
[tex]10,292.76=8,000(1+r)^{4}[/tex] Â
[tex](10,292.76/8,000)=(1+r)^{4}[/tex] Â
Elevated to 1/4 both sides to remove the exponent in the right side
[tex](10,292.76/8,000)^{1/4}=(1+r)[/tex] Â
[tex]r=(10,292.76/8,000)^{1/4}-1[/tex] Â
[tex]r=0.065[/tex] Â
Convert to percentage
[tex]r=6.5\%[/tex] Â