Algebra problem

Question

The enrollment at one Midwestern college is approximately by the formula

P=3000(1.08)^t

where t is the number of years after 2000. What is the first year in which you would expect enrollment to surpass 4200?

Answer 1

4200 = 3000(1.08)^t

42/30 = 7/5 = 1.4 = 1.08^t

log1.4 = tlog1.08

t = log1.4/log1.08

= about 4.37 years

= 2004+ or 2005