Answers

Add 45/72 and 72/80

45/72 + 72/80 is 61/40.

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,
   45/72 = 45 × 10/72 × 10 = 450/720
3. Likewise, for the 2nd fraction, since 80 × 9 = 720,
   72/80 = 72 × 9/80 × 9 = 648/720
4. Add the two like fractions:
   450/720 + 648/720 = 450 + 648/720 = 1098/720
5. 1098/720 simplified gives 61/40
6. So, 45/72 + 72/80 = 61/40
   In mixed form: 121/40

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