Adding integers is one of the important operations on integers, among the four fundamental operations on integers.

1. When the integers have like signs that is, when both the integers to be added are either positive or a negative.

Add their absolute values and assign the same sign to the sum.

Here, both the integers to be added are positive and their absolute values are 53 and 115 respectively.

The sum of their absolute values = 53 + 115 = 168

Therefore, (+53) + (+115) = +168

Here, both the numbers to be added are negative and their absolute values are 31 and 93 respectively.

The sum of their absolute values = 31 + 93 = 124

Therefore, (-31) + (-93) = -124

2. When the integers have unlike signs that is, one is positive and the other is negative.

Determine the difference of their absolute values and assign the sign of integer of greater absolute value.

(i) Add: + 47 and -27

The absolute values of +47 and -27 are 47 and 27 respectively; and their difference = 47 – 27 = 30.

Since, the integers with greater absolute value is 47 and it sign is ‘+’

Therefore, (+47) + (-27) = +30

The absolute values of -66 and +24 are 66 and 24 respectively; and their difference = 66 - 24 = 42.

Since, the integers with greater absolute value is 66 and it sign is ‘-’

Therefore, (-66) + (+24) = -42

(iii) Add: +253 and – 349

The absolute values of +253 and -349 are 253 and 349 respectively; and difference of their absolute values = 349 - 253 = 96

Since, the integers with greater absolute value is 349 and it sign is ‘-’

Therefore, (+253) + (-349) = -96.