Answer:
n = ㏒ P ÷ ㏒ (1.08)
Explanation:
Compound interest rate
A = P ×
where
P = principal amount (the initial amount you borrow or deposit)
r = annual rate of interest (as a decimal)
A = amount of money accumulated after n years, including interest.
n = number of years
Since we want the principle amount to double i.e., A = 2P
put this in above equation
2P = P ×
divide both sides by P, we get
P =
put r = 0.08
P =
P =
Taking log on both sides
㏒ P =㏒
㏒ P = n ㏒ (1.08)
n = ㏒ P ÷ ㏒ (1.08)