Answers

Add 21/90 and 70/63

1^st number: 21/90, 2^nd number: 1 7/63

21/90 + 70/63 is 121/90.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 63 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 90 × 7 = 630,
   21/90 = 21 × 7/90 × 7 = 147/630
3. Likewise, for the 2nd fraction, since 63 × 10 = 630,
   70/63 = 70 × 10/63 × 10 = 700/630
4. Add the two like fractions:
   147/630 + 700/630 = 147 + 700/630 = 847/630
5. 847/630 simplified gives 121/90
6. So, 21/90 + 70/63 = 121/90
   In mixed form: 131/90

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