Answers

Add 72/20 and 45/72

1^st number: 3 12/20, 2^nd number: 45/72

72/20 + 45/72 is 169/40.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 72 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 20 × 18 = 360,
   72/20 = 72 × 18/20 × 18 = 1296/360
3. Likewise, for the 2nd fraction, since 72 × 5 = 360,
   45/72 = 45 × 5/72 × 5 = 225/360
4. Add the two like fractions:
   1296/360 + 225/360 = 1296 + 225/360 = 1521/360
5. 1521/360 simplified gives 169/40
6. So, 72/20 + 45/72 = 169/40
   In mixed form: 49/40

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