Answers

Subtract 25/28 from 20/21

20/21 - 25/28 is 5/84.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 28 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 21 × 4 = 84,
   20/21 = 20 × 4/21 × 4 = 80/84
3. Likewise, for the 2nd fraction, since 28 × 3 = 84,
   25/28 = 25 × 3/28 × 3 = 75/84
4. Subtract the two like fractions:
   80/84 - 75/84 = 80 - 75/84 = 5/84

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