Answers

Subtract 40/49 from 21/40

21/40 - 40/49 is -571/1960.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 49 is 1960
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1960
2. For the 1st fraction, since 40 × 49 = 1960,
   21/40 = 21 × 49/40 × 49 = 1029/1960
3. Likewise, for the 2nd fraction, since 49 × 40 = 1960,
   40/49 = 40 × 40/49 × 40 = 1600/1960
4. Subtract the two like fractions:
   1029/1960 - 1600/1960 = 1029 - 1600/1960 = -571/1960

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