Answer:
28 years
Explanation:
To find the number of years that the investment will reach $3500, we can use the formula of compound interest:
P = Po * (1+r)^t
where P is the final value, Po is the inicial value, r is the annual interest and t is the time in years.
In this question, P = 3500, Po = 1800 and r = 2.46% = 0.0246, so:
3500 = 1800 * (1+0.0246)^t
1.0246^t = 3500/1800
1.0246^t = 1.9444
Using logarithm in both sides:
log(1.0246^t) = log(1.9444)
t*log(1.0246) = 0.2888
t * 0.0106 = 0.2888
t = 0.2888 / 0.0106 = 27.2453 years
So the investment will reach $3500 after 28 years (rounding the result up, because after 27 years the investment will not reach $3500)