Answers

Add 90/20 and 50/21

1^st number: 4 10/20, 2^nd number: 2 8/21

90/20 + 50/21 is 289/42.

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,
   90/20 = 90 × 21/20 × 21 = 1890/420
3. Likewise, for the 2nd fraction, since 21 × 20 = 420,
   50/21 = 50 × 20/21 × 20 = 1000/420
4. Add the two like fractions:
   1890/420 + 1000/420 = 1890 + 1000/420 = 2890/420
5. 2890/420 simplified gives 289/42
6. So, 90/20 + 50/21 = 289/42
   In mixed form: 637/42

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