Answers

Subtract 21/12 from 20/30

1^st number: 20/30, 2^nd number: 1 9/12

20/30 - 21/12 is -13/12.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 12 is 60
   
   Next, find the equivalent fraction of both fractional numbers with denominator 60
2. For the 1st fraction, since 30 × 2 = 60,
   20/30 = 20 × 2/30 × 2 = 40/60
3. Likewise, for the 2nd fraction, since 12 × 5 = 60,
   21/12 = 21 × 5/12 × 5 = 105/60
4. Subtract the two like fractions:
   40/60 - 105/60 = 40 - 105/60 = -65/60
5. After reducing the fraction, the answer is -13/12

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