Kristen invests $5,745 in a bank. the bank pays 6.5% interest compounded monthly. how long must she leave the money in the bank for it to double? round the nearest tenth of a year.

formula is

where A=final amount

P=principal

r=interest rate in decimal

n=number of times per year it is compounded

t=time in years

we want to find where

A=2P

and P=5745

and r=6.5%=0.065

n=monthly=12

remember that

also that

, solving for t

divide both sides by 5745 to simplify things a bit

I'd rather not simplify this because it give us a decimals and those aren't exact, if we combine, we get 12.065/12 for inside parenthases

take ln of both sides

divide both sides by

using our calculator, t≈10.6927

so rounded, we get 10.7 years

this shows a reflection over the x-axis and is translated one unit down and 6 units to the right (x + 6, y - 1)

hope this !

~just a girl in love with shawn mendes