i understand part 1 but i forgot how to get part 2 any help!?

Question

anonymous · Answer

attachment

campbell_st · Answer

use either formula to find the investment for the time period found in part 1...

campbell_st · Answer

its just looking for the value of the investments when there are equal in value

anonymous · Answer

ive been trying to get it, do you mind showing me how to get the part 2 value??

campbell_st · Answer

so using $$A = Pe^{rt} $$


Bobs Bank 

$$A=5000e^{0.12t}$$

Charlies Bank

$$A = 7000e^{0.03t}$$

let then be equal to find t

$$5000e^{0.12t} = 7000e^{0.03t}$$

$$e^{0.09t} = \frac{7000}{5000}$$

$$t = 100/9\times \ln(7/5)$$

t = 3.73858

is when the investments have the same value

Part 2

which is 

$$A = 5000e^{0.12\times3.73858}$$

the future value is $7830.82 when t = 3.73858

anonymous · Answer

thanks a lot

campbell_st · Answer

thats ok... hope it helped