24000=12000(1+ 4/100)^t divide both sides by 12000
24000/12000 = (1 + .04)^t
2 = (1.04)^t take the log of both sides
log (2) = log (1.04)^t and we can write
log (2) = t * log(1.04) divide both sides by log (1.04)
log(2) / log (1.04) = t = about 17.673
