Answers

Add 90/72 and 20/80

1^st number: 1 18/72, 2^nd number: 20/80

90/72 + 20/80 is 3/2.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 80 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 72 × 10 = 720,
   90/72 = 90 × 10/72 × 10 = 900/720
3. Likewise, for the 2nd fraction, since 80 × 9 = 720,
   20/80 = 20 × 9/80 × 9 = 180/720
4. Add the two like fractions:
   900/720 + 180/720 = 900 + 180/720 = 1080/720
5. 1080/720 simplified gives 3/2
6. So, 90/72 + 20/80 = 3/2
   In mixed form: 11/2

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