A car brought for £22000 depreciates in value by 8% each year. After how many years is the car worth less than half of it's original value?
1 - 8% =92%
11,000 =22,000 x (0.92^n) divide both sides by 22,000
1/2 =.92^n take the log of both sides
n =Log(1/2) / Log(.92)
n=8.31 years - Just over 8 1/3 years, the car will be worth LESS than 1/2 its original value.