.955 not .995
B 7000 = 8500 (.955)^t solve for t (the number of years past 2010)
7000 = 8500(.955)^t divide both sides by 8500
7000/8500 = .955^t
7000/8500 = .955^t take the log of both sides
log (7000/8500) = log (.955)^t and we can write
log (7000/8500) = t * log (.955) divide both sides by log(.955)
log (7000/8500) / log (.955) = t ≈ 4.2 years after 2010 = 2014
I could be overthinking this, but wouldn't 4.2 years after 2010 be 2015?
4 years after 2010 would certainly land in 2014, but the extra .2 years would spill over into the year 2015.