Answers

Add 70/21 and 90/20

1^st number: 3 7/21, 2^nd number: 4 10/20

70/21 + 90/20 is 47/6.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 20 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 21 × 20 = 420,
   70/21 = 70 × 20/21 × 20 = 1400/420
3. Likewise, for the 2nd fraction, since 20 × 21 = 420,
   90/20 = 90 × 21/20 × 21 = 1890/420
4. Add the two like fractions:
   1400/420 + 1890/420 = 1400 + 1890/420 = 3290/420
5. 3290/420 simplified gives 47/6
6. So, 70/21 + 90/20 = 47/6
   In mixed form: 75/6

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