Question

If you deposit $1000 in a savings account with an interest rate of r compounded annually, then the balance in the account after 3 years is given by the function B(c) = 1000(1 + r)3, where r is written as a decimal.

What interest rate will yield a balance of $1100 after 3 years?



a.

3.23%

c.

3.63%


b.

3.33%

d.

3.66%

Answer 1

help me out please!

Answer 2

The amount in the savings account is given by the function. So, we just set $1100 equal to the equation and solve for r:
\[1100=1000(1+r)^3\]Divide both sides by 1000:
\[1.1=(1+r)^3\]Cube root both sides:
\[1.03228=1+r\]Subtract r from both sides:
\[r=.03228\]

Answer 3

thanks!