Question

HELP:
The formula A=P(1+r)^2 gives the amt A in dollars, that P dollars will grow to in 2 years at interest rated r (where r is given as a decimal), using the compound interest?

What interest rate will cause 6000 to grow into 6678.15 in two years?

I am stuck.
A=P(1+r)^2
6678.15=6000(1+r)^2

6678.15/6000=(1+r)^2
1.11302=(1+r)^2

I am stuck at this point!

Answer 1

(1 + r)^2 = 1.11302
1 + r = sqrt(1.11302)
r = sqrt(1.11203) - 1
its now calculator time

Answer 2

sorry thats sqrt(1.11302) - 1
= .055 or 5.5 %

Answer 3

A=P(1+r)^2
-> (1 + r )^2 = A/P
-> 1 + r = sqrt (A/P)
=> r = sqrt [(A/P) - 1 ]
Thus rate = sqrt (6678.15 / 6000 ) - 1 = 11.3%

Answer 4

i think your calculation is wrong chlorophyll

Answer 5

Yes, I'm testing why. Thanks

Answer 6

Sorry!
sqrt (6678.15 / 6000 ) = 1.055
r = 1.055 -1 = .055 = 5.5%

Answer 7

thats ok - good job

Answer 8

I really learn a lot from other solvers like you :)

Answer 9

glad to hear it - thats what this site is for