Among the fractions given in this question 11/18 and 5/14, the largest fraction is: 3/5.
To find out which fraction is the largest, just divide the numerator by the denominator of the ratio and make the comparisons between them, thus defining which is the largest by decimal places or the largest number.
We can conclude that the largest fraction, being between 11/18 and 5/14, is 11/18.