Answers

Subtract 72/80 from 90/72

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

90/72 - 72/80 is 7/20.

Steps for subtracting 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,
   72/80 = 72 × 9/80 × 9 = 648/720
4. Subtract the two like fractions:
   900/720 - 648/720 = 900 - 648/720 = 252/720
5. After reducing the fraction, the answer is 7/20

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