Answers

Add 21/72 and 40/20

1^st number: 21/72, 2^nd number: 2 0/20

21/72 + 40/20 is 55/24.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 20 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 72 × 5 = 360,
   21/72 = 21 × 5/72 × 5 = 105/360
3. Likewise, for the 2nd fraction, since 20 × 18 = 360,
   40/20 = 40 × 18/20 × 18 = 720/360
4. Add the two like fractions:
   105/360 + 720/360 = 105 + 720/360 = 825/360
5. 825/360 simplified gives 55/24
6. So, 21/72 + 40/20 = 55/24
   In mixed form: 27/24

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