Answers

Subtract 21/20 from 18/56

1^st number: 18/56, 2^nd number: 1 1/20

18/56 - 21/20 is -51/70.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 56 and 20 is 280
   
   Next, find the equivalent fraction of both fractional numbers with denominator 280
2. For the 1st fraction, since 56 × 5 = 280,
   18/56 = 18 × 5/56 × 5 = 90/280
3. Likewise, for the 2nd fraction, since 20 × 14 = 280,
   21/20 = 21 × 14/20 × 14 = 294/280
4. Subtract the two like fractions:
   90/280 - 294/280 = 90 - 294/280 = -204/280
5. After reducing the fraction, the answer is -51/70

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