Answer:
9.9 years
Step-by-step explanation:
A = P e ^(rt)
Where A is the amount in the account
P is the amount invested
R is the interest rate
t is the time
P = 8500
r =7% = .07
A = 17000
Substituting into the equation
17000=8500 e^(.07t)
Divide each side by 8500
17000/8500=8500/8500 e^(.07t)
2 = e^(.07t)
Take the natural log of each side
ln (2) = ln e^(.07t)
ln(2) = .07t
Divide each side by .07
ln(2)/.07 = .07t/.07
ln(2)/.07 = t
9.902102579=t
Rounding to one decimal place
9.9 years
All you need to do is find (f+g)x = (12x) + (10(1.2)X) which = 24x
then in the multiple choice, see which one equals 24x, in this case its C.
5*1.2=6, 6x+6x = 12x*2 = 24x
It is 109
Hope it helps !!
