Answers

Subtract 21/20 from 42/56

1^st number: 42/56, 2^nd number: 1 1/20

42/56 - 21/20 is -3/10.

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,
   42/56 = 42 × 5/56 × 5 = 210/280
3. Likewise, for the 2nd fraction, since 20 × 14 = 280,
   21/20 = 21 × 14/20 × 14 = 294/280
4. Subtract the two like fractions:
   210/280 - 294/280 = 210 - 294/280 = -84/280
5. After reducing the fraction, the answer is -3/10

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