A = Pert,
where P is the initial investment and r is the interest rate.
What rate of interest compounded continuously is needed for an investment of $500 to grow to $900 in 10 years? show work plz

Question

A = Pert,
where P is the initial investment and r is the interest rate. 
What rate of interest compounded continuously is needed for an investment of $500 to grow to $900 in 10 years? show work plz

dumbcow · Answer

well
P = 500
A = 900
t =10
solve for r
$$900 = 500e^{10r}$$
divide by 500
$$e^{10r} = 9/5$$
take natural log of both sides
$$10r = \ln (9/5)$$
divide by 10
$$r = \frac{\ln (9/5)}{10}$$

dumbcow · Answer

did you follow that?

anonymous · Answer

Theres suppose to be a simplier answer apparently and I dont get how you take in9/5
                                                                                                                             ---                                                                                                                               10

dumbcow · Answer

just put it in your calculator
ln(9/5) = .5877

dumbcow · Answer

im guessing they want it as a percent
multiply r by 100 then

anonymous · Answer

thank you so much!