Answers

Add 64/21 and 28/20

1^st number: 3 1/21, 2^nd number: 1 8/20

64/21 + 28/20 is 467/105.

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,
   64/21 = 64 × 20/21 × 20 = 1280/420
3. Likewise, for the 2nd fraction, since 20 × 21 = 420,
   28/20 = 28 × 21/20 × 21 = 588/420
4. Add the two like fractions:
   1280/420 + 588/420 = 1280 + 588/420 = 1868/420
5. 1868/420 simplified gives 467/105
6. So, 64/21 + 28/20 = 467/105
   In mixed form: 447/105

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