Determine how long in years it will take the value of a motor vehicle to decrease to 25% of its original value if the rate of depreciation based on the reducing balance method is 21% per annum?

Answer 1

100 (1- .21)^t = 25

.79^t = .25
log (.79^t) = log .25
t log.79 = log.25
t = log.25/log.79 = 13.66
about 13 and 2/3 years

Answer 2

1.6