Question 1020461
Hi there,
N(t) =390000(.5)^t
60000 = 390000(.5)^t
60000/390000 = (.5)^t
0.153846 = (.5)^t
log 0.153846 log(.5)^t
log 0.153846 = t log(.5)
t = log 0153846/log (.5)
t = 2.7
2.7 years
Hope this helps :-)