Question

Suppose $4,100 is invested in an account at an annual interest rate of 6.6% compounded
continuously. How long (to the nearest tenth of a year) will it take the investment to double in
size?

Answer 1

Formula for Continuous Compounding is:
\[A = Pe^{rt}\]

Answer 2

thank you

Answer 3

im just trying to understand how to input the information into the formula

Answer 4

A = 8,200
P = 4,100
e = euler's number
r = .066
t = what we need to find

Answer 5

p(t)=4000e0.066t?

Answer 6

\[8,200 = 4,100e^{.066t}\]

Answer 7

Solve for \(t\)

Answer 8

\[8200=41000e ^{.066t}\]

Answer 9

please explain the 8200

Answer 10

It's double the 4,100

Answer 11

right

Answer 12

It asks how long it would take for 4,100 to double. Obviously 8,200 is double 4,100

Answer 13

ahhh i get it now

Answer 14

46 years?

Answer 15

did I calculate it wrong?

Answer 16

or 46.8?

Answer 17

How did you get that? 46.8 isn't even close

Answer 18

ithink I miss calculated . used my calculator

Answer 19

What kind of calculator do you have?

Answer 20

trying again

Answer 21

Microsoft mathematics

Answer 22

Try to isolate t on paper first. Then input the expression for t unto your calc.

Answer 23

im thinking that is where i made the mistake

Answer 24

Where did you get a Microsoft Mathematics calculator?

Answer 25

online computer software not a physical calculator

Answer 26

ok if 10.5 years is not correct I may need more guidance

Answer 27

That is correct. Great job

Answer 28

Thanks!!!

Answer 29

if you google Microsoft Mathematics you should be able to get it, i think its free

Answer 30

I already have a graphing calc. TI-Nspire CX.

Answer 31

ok cool