Answers

Add 21/80 and 7/72

21/80 + 7/72 is 259/720.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 72 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 80 × 9 = 720,
   21/80 = 21 × 9/80 × 9 = 189/720
3. Likewise, for the 2nd fraction, since 72 × 10 = 720,
   7/72 = 7 × 10/72 × 10 = 70/720
4. Add the two like fractions:
   189/720 + 70/720 = 189 + 70/720 = 259/720
5. So, 21/80 + 7/72 = 259/720

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