Answers

Subtract 40/21 from 20/63

1^st number: 20/63, 2^nd number: 1 19/21

20/63 - 40/21 is -100/63.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 63 and 21 is 63
   
   Next, find the equivalent fraction of both fractional numbers with denominator 63
2. For the 1st fraction, since 63 × 1 = 63,
   20/63 = 20 × 1/63 × 1 = 20/63
3. Likewise, for the 2nd fraction, since 21 × 3 = 63,
   40/21 = 40 × 3/21 × 3 = 120/63
4. Subtract the two like fractions:
   20/63 - 120/63 = 20 - 120/63 = -100/63

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