Answers

Add 21/30 and 81/63

1^st number: 21/30, 2^nd number: 1 18/63

21/30 + 81/63 is 139/70.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 63 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 30 × 21 = 630,
   21/30 = 21 × 21/30 × 21 = 441/630
3. Likewise, for the 2nd fraction, since 63 × 10 = 630,
   81/63 = 81 × 10/63 × 10 = 810/630
4. Add the two like fractions:
   441/630 + 810/630 = 441 + 810/630 = 1251/630
5. 1251/630 simplified gives 139/70
6. So, 21/30 + 81/63 = 139/70
   In mixed form: 169/70

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