In the log table , we find the number 25 in the left-hand column. In the row, in the next column ( under 0) , we find 0.3979 . (the decimal point is dropped in other columns)
For the log all numbers whose significant digits are 25 and this number 0.3979 , is the mantissa , prefixing the characteristics we have.
log25= 1.3979
log250 = 2.3979
log 0.025 = `overline2.3979`
