Use logarithms to solve the equation 2^(n-3) = 18000, giving your answer correct to 3 significant figures.
To find the answer first you have to take a log of both sides.
I am going to use log to the base 2 for my example - but any base will work as long as they are the same on both sides of the equals sign
log(2n-3)=log(18000)
Using the rules of logerithms you can bring down the power
(n-3)log(2)=log(18000)
As I am using base 2 log(2)=1
n-3=log(18000)
n=log(18000)+3
n=17.1
EJ
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