Answers

Subtract 49/40 from 1/21

1^st number: 1/21, 2^nd number: 1 9/40

1/21 - 49/40 is -989/840.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 40 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 21 × 40 = 840,
   1/21 = 1 × 40/21 × 40 = 40/840
3. Likewise, for the 2nd fraction, since 40 × 21 = 840,
   49/40 = 49 × 21/40 × 21 = 1029/840
4. Subtract the two like fractions:
   40/840 - 1029/840 = 40 - 1029/840 = -989/840

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