Answers

Subtract 20/56 from 7/21

7/21 - 20/56 is -1/42.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 56 is 168
   
   Next, find the equivalent fraction of both fractional numbers with denominator 168
2. For the 1st fraction, since 21 × 8 = 168,
   7/21 = 7 × 8/21 × 8 = 56/168
3. Likewise, for the 2nd fraction, since 56 × 3 = 168,
   20/56 = 20 × 3/56 × 3 = 60/168
4. Subtract the two like fractions:
   56/168 - 60/168 = 56 - 60/168 = -4/168
5. After reducing the fraction, the answer is -1/42

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