Answers

Add 90/20 and 20/84

1^st number: 4 10/20, 2^nd number: 20/84

90/20 + 20/84 is 199/42.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 84 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 84 × 5 = 420,
   20/84 = 20 × 5/84 × 5 = 100/420
4. Add the two like fractions:
   1890/420 + 100/420 = 1890 + 100/420 = 1990/420
5. 1990/420 simplified gives 199/42
6. So, 90/20 + 20/84 = 199/42
   In mixed form: 431/42

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