Answers

Subtract 40/49 from 20/21

20/21 - 40/49 is 20/147.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 49 is 147
   
   Next, find the equivalent fraction of both fractional numbers with denominator 147
2. For the 1st fraction, since 21 × 7 = 147,
   20/21 = 20 × 7/21 × 7 = 140/147
3. Likewise, for the 2nd fraction, since 49 × 3 = 147,
   40/49 = 40 × 3/49 × 3 = 120/147
4. Subtract the two like fractions:
   140/147 - 120/147 = 140 - 120/147 = 20/147

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