Number analogy section deals with two types of questions:
I. Choosing a similarly related pair as the given number pair on the basis of the relation between the numbers in each pair.
II. Choosing a number similar to a group of numbers on the basis of certain common properties that they possess.
Given set : 538, 725, 813
In all the numbers, (1st digit + 3rd digit) - middle digit = 10
Thus, 5 + 8 - 3 = 10, 7 + 5 - 2 = 10, 8 + 3 - 1 = 10.