Chapter 5 - Operations on Rational Numbers - R D Sharma Solutions for Class 7
There are two cases:
Case 1: If the rational numbers have same denominators, then we will add as follows: pq+rq=p+rq
Case 2: If the rational numbers have different denominators, then first we will make the denominator positive and then make the denominations same by taking their LCM and then add using case 1.