Solve.
-Find out how long it takes a $\$ 3100$ investment to double if it is invested at $8 \%$ compounded semiannually. Round to the nearest tenth of a year. Use the formula $A = P \left( 1 + \frac { r } { n } \right) ^ { n t }$.
A) $8.6$ years
B) 9 years
C) $9.2$ years
D) $8.8$ years

Question

Quizplus · Accepted Answer

Using the formula $A = P \left( 1 + \frac { r } { n } \right) ^ { n t }$, where $A = 6200$, $P = 3100$, $r = 0.08$, and $n = 2$, solve for $t$. The equation becomes $6200 = 3100 \left( 1 + \frac {0.08}{2} \right)^{2t}$. Simplifying gives $2 = \left(1.04\right)^{2t}$. Taking the natural logarithm of both sides and solving for $t$ gives $t \approx 8.8$ years.

Solve -Find Out How Long It Takes A $3100\$ 3100$3100 Investment to Double If It Is Invested At

Solve
-Find Out How Long It Takes A $\$ 3100$ Investment to Double If It Is Invested At