Help me find the time t please! Problem: If Joenita invests $1500 into a retirement account with an 8% interest rate compounded quarterly, how long will it take to grow to $3750?

Question

anonymous · Answer

I already know that the r=8%=.08 and k=4(quarterly)

camper4834 · Answer

well we have a formula for this
$$A = P (1+\frac{ r }{ n } )^{ nt } $$

camper4834 · Answer

http://www.mathwarehouse.com/compound-interest/images/formula-compound-interest.png A = 3750 P = 1500 r = .08 n = 4 t is what we are looking for

anonymous · Answer

Oh that's right. Thank you :)

camper4834 · Answer

did you get the answer?

anonymous · Answer

Yeah. Its t=11.5677924723 and reduced to 11.57 yrs correct?

camper4834 · Answer

let me double check for some reason i didn't get that

anonymous · Answer

In my textbook, the answer in the back of the book is 11.75 yrs so I may be a bit off but close enough. Did you do log?

camper4834 · Answer

i did. your answer is correct. idk what i did wrong though

anonymous · Answer

Did you do log(3750/1500)/(4log(1.02))?

camper4834 · Answer

ahh i messed up on (1+.08/4)

camper4834 · Answer

instead of 1+.02 i did 1+.2

anonymous · Answer

oh ok