The rule is: If asked for 4 decimal places look at the 5th figure. If it is 5 or more put the 4th number up by 1
This example should explain. Write 3.68 correct to one decimal place. The answer is 3.7 because 3.68 is nearer to 3.7 than it is to 3.6
When I use a calculator to log 8, I get .903089986991944, and i am suppose to take four numbers after the decimal. So, I get .9030... However the answer is suppose to be .9031. I have noticed that a lot, the last number seems to always be 1 number lower(the 4th number after the decimal). Is that common?
The rule is: If asked for 4 decimal places look at the 5th figure. If it is 5 or more put the 4th number up by 1
This example should explain. Write 3.68 correct to one decimal place. The answer is 3.7 because 3.68 is nearer to 3.7 than it is to 3.6
x = the number (.903089986991944)
n = number of digits after decimal point (4)
x = |x*10^n + .5| / 10^n ; that'll give you .9031
By the way, your question has really nothing to do with logs;
it's about "rounding".