Convert the mixed fraction into an improper fraction. Multiply the denominator by the whole number and add the result to the numerator. Complete the conversion by putting the result over the initial denominator. If the fraction is already improper or proper, do not perform any conversion yet.
Divide the denominator of the fraction by the numerator by using the long-division method. Continue the division until it eventually terminates. In case it does not terminate, stop when you reach the fourth decimal place such as 24.5544.
Round the decimal to three places. To do this, check the fourth decimal number. If it is five or more, add one to the third decimal number. If it is four or less, ignore the fourth decimal figure. In this case, the number 24.5544 becomes 24.554 when rounded off.
Observe the figure before the decimal point. If it is greater than nine, take the decimal point so that it is just after the first digit. In this case, the number becomes 2.4555. Since three decimal points are required in this example, the number changes to 2.456. Adjust the figure to have the original value by multiplying the new number by base 10 raised to a power that denotes the amount of places the decimal point retreated.
Locate the position of the first two digits --- 2.4 --- on the first column of the log table. Run your eyes along that row and observe the decimal figure bearing the hundredths-place value (5) on the second column. Record this figure on a piece of paper. Look for the logarithmic value of the last decimal point figure (6) on the third column and add it to the logarithmic figure you had earlier obtained. Adjust your logarithmic value by replacing the zero at the front with the power if you moved the decimal point. You now have your logarithm.