Answers

Subtract 21/18 from 90/80

1^st number: 1 10/80, 2^nd number: 1 3/18

90/80 - 21/18 is -1/24.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 18 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 80 × 9 = 720,
   90/80 = 90 × 9/80 × 9 = 810/720
3. Likewise, for the 2nd fraction, since 18 × 40 = 720,
   21/18 = 21 × 40/18 × 40 = 840/720
4. Subtract the two like fractions:
   810/720 - 840/720 = 810 - 840/720 = -30/720
5. After reducing the fraction, the answer is -1/24

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