Answers

Subtract 75/21 from 20/40

1^st number: 20/40, 2^nd number: 3 12/21

20/40 - 75/21 is -43/14.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 21 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 40 × 21 = 840,
   20/40 = 20 × 21/40 × 21 = 420/840
3. Likewise, for the 2nd fraction, since 21 × 40 = 840,
   75/21 = 75 × 40/21 × 40 = 3000/840
4. Subtract the two like fractions:
   420/840 - 3000/840 = 420 - 3000/840 = -2580/840
5. After reducing the fraction, the answer is -43/14

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