Answers

Subtract 84/80 from 72/90

1^st number: 72/90, 2^nd number: 1 4/80

72/90 - 84/80 is -1/4.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 80 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 90 × 8 = 720,
   72/90 = 72 × 8/90 × 8 = 576/720
3. Likewise, for the 2nd fraction, since 80 × 9 = 720,
   84/80 = 84 × 9/80 × 9 = 756/720
4. Subtract the two like fractions:
   576/720 - 756/720 = 576 - 756/720 = -180/720
5. After reducing the fraction, the answer is -1/4

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