Question

Joe deposits $630 in a savings account which pays 5.5% per year. If the account compounds monthly, find how long it takes to double his investment.

Answer 1

Well he gets 34.65 from it, so it would take 19 months

Answer 2

how did you figure

Answer 3

11.5 years

10.7 years

12.6 years

14.3 years

Answer 4

those are my choices

Answer 5

though

Answer 6

You can use this equation to solve:
\[1260=630(1+\frac{0.055}{12})^{12t}\]
where t is the number of years.
Do you know how to solve for t?

Answer 7

you times 12 into 0.055 and 12?

Answer 8

or divide?

Answer 9

12.63?

Answer 10

so its 12.6 years

Answer 11

First divide both sides by 630 and simplify the terms inside the brackets to give:
\[2=1.00457^{12t}\]
Then take logs of both sides:
\[\log_{} 2=12t \log_{} 1.00457\]
Now divide both sides by 12 * lo1.00457 to get:
\[t=\frac{\log\ 2}{12\ \log\ 1.00457}=you\ can\ calculate\]

Answer 12

I dont undersand this

Answer 13

I thought the answer was 12.6

Answer 14

Did you do the calculation?

Answer 15

idk

Answer 16

ok hold on

Answer 17

t = 12.67 years

Answer 18

so c 12.6? thats my option