174k views
1 vote
I tried 9.90 but that doesn't work, please help

I tried 9.90 but that doesn't work, please help-example-1
User Rozuur
by
7.2k points

1 Answer

2 votes
Using the formula for compound interest, where:

A = final amount = 15100 dollars
P = principal = 9000 dollars
r = annual interest rate = 5.5%
n = number of times interest is compounded per year (usually monthly or quarterly, but not specified in the problem)
t = time in years

We have:

15100 = 9000(1 + 0.055/n)^(nt)

To solve for t, we need to use logarithms:

ln(15100/9000) = t ln(1 + 0.055/n)

t = ln(15100/9000) / ln(1 + 0.055/n)

Using a calculator, we get:

t ≈ 6.68 years

Therefore, the person must leave the money in the bank for approximately 6.68 years to reach 15100 dollars.
User Magoo
by
8.4k points

No related questions found