Answers

Subtract 40/21 from 30/42

1^st number: 30/42, 2^nd number: 1 19/21

30/42 - 40/21 is -25/21.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 21 is 42
2. For the 1st fraction, since 42 × 1 = 42,
   30/42 = 30 × 1/42 × 1 = 30/42
3. Likewise, for the 2nd fraction, since 21 × 2 = 42,
   40/21 = 40 × 2/21 × 2 = 80/42
4. Subtract the two fractions:
   30/42 - 80/42 = 30 - 80/42 = -50/42
5. After reducing the fraction, the answer is -25/21

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