Answers

Add 72/90 and 70/21

1^st number: 72/90, 2^nd number: 3 7/21

72/90 + 70/21 is 62/15.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 21 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 90 × 7 = 630,
   72/90 = 72 × 7/90 × 7 = 504/630
3. Likewise, for the 2nd fraction, since 21 × 30 = 630,
   70/21 = 70 × 30/21 × 30 = 2100/630
4. Add the two like fractions:
   504/630 + 2100/630 = 504 + 2100/630 = 2604/630
5. 2604/630 simplified gives 62/15
6. So, 72/90 + 70/21 = 62/15
   In mixed form: 42/15

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