Answers

Subtract 40/21 from 10/42

1^st number: 10/42, 2^nd number: 1 19/21

10/42 - 40/21 is -5/3.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 21 is 42
   
   Next, find the equivalent fraction of both fractional numbers with denominator 42
2. For the 1st fraction, since 42 × 1 = 42,
   10/42 = 10 × 1/42 × 1 = 10/42
3. Likewise, for the 2nd fraction, since 21 × 2 = 42,
   40/21 = 40 × 2/21 × 2 = 80/42
4. Subtract the two like fractions:
   10/42 - 80/42 = 10 - 80/42 = -70/42
5. After reducing the fraction, the answer is -5/3

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