Answers

Add 15/20 and 56/21

1^st number: 15/20, 2^nd number: 2 14/21

15/20 + 56/21 is 41/12.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 21 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 20 × 21 = 420,
   15/20 = 15 × 21/20 × 21 = 315/420
3. Likewise, for the 2nd fraction, since 21 × 20 = 420,
   56/21 = 56 × 20/21 × 20 = 1120/420
4. Add the two like fractions:
   315/420 + 1120/420 = 315 + 1120/420 = 1435/420
5. 1435/420 simplified gives 41/12
6. So, 15/20 + 56/21 = 41/12
   In mixed form: 35/12

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