$3550 $ ⁢ 3550 is invested at 10.0% 10.0 % compounded continuously. How long will it take for the balance to reach $7100 $ ⁢ 7100 ? Round your answer to two decimal places, if necessary.

Respuesta :

Answer:

6.93 years.

Step-by-step explanation:

We have been given that $3550 is invested at 10.0% compounded continuously.

To solve our given problem, we will use continuous compounding formula.

[tex]A=P\cdot e^{rt}[/tex], where,

A = Final amount,

P = Principal amount,

e = Mathematical constant,

r = Interest rate in decimal form,

t = Time

[tex]10\%=\frac{10}{100}=0.10[/tex]

Substitute the given values:

[tex]7100=3550\cdot e^{0.10t}[/tex]

[tex]\frac{7100}{3550}=\frac{3550\cdot e^{0.10t}}{3550}[/tex]

[tex]2=e^{0.10t}[/tex]

Take natural log of both sides:

[tex]\text{ln}(2)=\text{ln}(e^{0.10t})[/tex]

Using property [tex]\text{ln}(a^b)=b\cdot \text{ln}(a)[/tex], we will get:

[tex]\text{ln}(2)=0.10t\cdot \text{ln}(e)[/tex]

[tex]0.6931471805599453=0.10t\cdot 1[/tex]

[tex]0.6931471805599453=0.10t[/tex]

Switch sides:

[tex]0.10t=0.6931471805599453[/tex]

[tex]\frac{0.10t}{0.10}=\frac{0.6931471805599453}{0.10}[/tex]

[tex]t=6.9314718[/tex]

[tex]t\approx 6.93[/tex]

Therefore, it will take approximately 6.93 years for the balance to reach $7100.