John invested $8,400 in an account paying an interest rate of 3% compounded continuously. Sarah invested $8,400 in an account paying an interest rate of 4%
compounded quarterly. To the nearest dollar, how much money would John have in
his account when Sarah's money has tripled in value?

597

step-by-step explanation:

step-by-step explanation:

the ratio of red paint to blue paint is always 9/7. that means that, whatever x's value, (4x+12)/(4x-4) has that same ratio. so, set up an equation and cross-multiply to solve for x:

9/7 = (4x+12)/(4x-4)

9(4x-4) = 7(4x+12)

36x - 36 = 28x + 84

8x - 36 = 84

8x = 120

x = 15