Answer:
7 years (to the nearest year)
Step-by-step explanation:
Given that;
A = amount
P= principal
t = time
r = rate
A =3P(given in the question)
Formula for compound interest;
A = P(1 + r)^t
Substituting values;
3P = P(1 + 18/100)^t
3P/P= (1.18)^t
3 = (1.18)^t
log 3 = t log 1.18
t = log 3/log 1.18
t = 0.4771/0.0719
t = 6.6 years
t = 7 years (to the nearest year)