Answer:
W = 54.7*e^0.038t
11.6 years
Step-by-step explanation:
Given that :
Initial value = 54.7 trillion dollars
Continuous Growth rate (r) = 3.8% = 0.038
Using the exponential growth model formula :
W = P0*e^kt
Where ;
y = final amount ; P0 = initial value ; t = time ; k = growth rate constant
W = 54.7*e^0.038t
Value of t when W = 85 trillion
W = 85
85 = 54.7*e^0.038t
85 / 54.7 = e^0.038t
1.5539305 = e^0.038t
Take In of both sides
0.4407875 = 0.038t
Divide both sides by 0.038
t = 11.599672
t = 11.6 years