Answers

Add 21/45 and 80/72

1^st number: 21/45, 2^nd number: 1 8/72

21/45 + 80/72 is 71/45.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 45 and 72 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 45 × 8 = 360,
   21/45 = 21 × 8/45 × 8 = 168/360
3. Likewise, for the 2nd fraction, since 72 × 5 = 360,
   80/72 = 80 × 5/72 × 5 = 400/360
4. Add the two like fractions:
   168/360 + 400/360 = 168 + 400/360 = 568/360
5. 568/360 simplified gives 71/45
6. So, 21/45 + 80/72 = 71/45
   In mixed form: 126/45

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