Answers

Add 90/12 and 70/21

1^st number: 7 6/12, 2^nd number: 3 7/21

90/12 + 70/21 is 65/6.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 12 and 21 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 12 × 7 = 84,
   90/12 = 90 × 7/12 × 7 = 630/84
3. Likewise, for the 2nd fraction, since 21 × 4 = 84,
   70/21 = 70 × 4/21 × 4 = 280/84
4. Add the two like fractions:
   630/84 + 280/84 = 630 + 280/84 = 910/84
5. 910/84 simplified gives 65/6
6. So, 90/12 + 70/21 = 65/6
   In mixed form: 105/6

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