Answers

Add 28/21 and 40/20

1^st number: 1 7/21, 2^nd number: 2 0/20

28/21 + 40/20 is 10/3.

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,
   28/21 = 28 × 20/21 × 20 = 560/420
3. Likewise, for the 2nd fraction, since 20 × 21 = 420,
   40/20 = 40 × 21/20 × 21 = 840/420
4. Add the two like fractions:
   560/420 + 840/420 = 560 + 840/420 = 1400/420
5. 1400/420 simplified gives 10/3
6. So, 28/21 + 40/20 = 10/3
   In mixed form: 31/3

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