Solution:
A = P(1+r)^n
where,
A = amount
P = principal
r = rate of interest
n = number of years
Putting values in the formula,
8850 = 2750(1+0.08)^n
8850/2750 = (1+0.08)^n
log will be used to solve "n" as it is in the exponent form, which gives,
log(8850/2750) = n log(1+0.08)
By solving, we get n = log(8850/2750) / log(1+0.08)
Using financial calculator, value comes as 15.187 rounded to 15.19.
So, he will have to wait for 15.19 years to take holidays as it will take 15.19 years to make $8850 from $2750 @ 8% annual compounding.