Ryan invests $7,171 in a savings account with a fixed annual interest rate of 7% compounded 12 times per year. How long will it take for the account balance to reach $11,688.69?

Round your answer to the nearest whole year.

Respuesta :

It will take 7 years for the account balance to reach $11,688.69.

To find how long will it take for the account balance to reach $11,688.69

we will use the compound interest formula that is

[tex]$ \text A = \text P(1 + \frac{\text r}{\text n})^{\text {nt}}[/tex]

where,

A = final amount

P = initial principal balance

r = interest rate

n = number of times interest applied per time period

t = number of time periods elapsed

Given that, P = $7,171

A = $11,688.69

r = 7%

n = 12

t = to find

Substitute the details in the formula and we get

[tex]$11688.69 = 7171(1 + \frac{0.07}{12})^{12t}[/tex]

[tex]$ \text t=\frac{\log _{\frac{1207}{1200}}\left(\frac{1168869}{717100}\right)}{12}[/tex]

t = 7.000003 = 7 years

Thus, It will take 7 years  for the account balance to reach $11,688.69.

Learn more about compound interest

https://brainly.com/question/29335425

Answer:

  • 7 years

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Use compound interest equation:

  • A = P(1 + r/n)^(nt), where A - future amount, P- investment, r - interest rate, n- number of compounds, t - time in years

Substitute the given to find the value of t:

  • 11688.69 = 7171(1 + 0.07/12)^(12t)
  • 1.0058333333^(12t) = 11688.69 /7171
  • 1.0058333333^(12t)  = 1.62999442198
  • ln 1.0058333333^(12t)  = ln 1.62999442198
  • 12t = ln 1.62999442198 / ln 1.0058333333
  • 12t = 84 (rounded)
  • t = 7