Doug C. answered 09/05/22
Math Tutor with Reputation to make difficult concepts understandable
Given 100.69897=5 (this is a close approximation), if we multiply both sides by 100 we will be in a position to determine the log 500. Since 100 = 102, the multiplication looks like this:
102100.69897=5(100)
One the left since we are multiplying powers with the same base the exponents can be added:
102.69897=500
By inspection it is apparent that the exponent that you apply to a base of 10 to produce 500 is 2.69897.
If that is not so easy to see try taking the log of both sides:
log 102.69897= log 500
2.69897 log 10 = log 500 (power property of logarithms)
2.69897 (1) = log 500 (log 10 = 1)