Answers

Subtract 90/21 from 1/42

1^st number: 1/42, 2^nd number: 4 6/21

1/42 - 90/21 is -179/42.

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,
   1/42 = 1 × 1/42 × 1 = 1/42
3. Likewise, for the 2nd fraction, since 21 × 2 = 42,
   90/21 = 90 × 2/21 × 2 = 180/42
4. Subtract the two like fractions:
   1/42 - 180/42 = 1 - 180/42 = -179/42

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