Answers

Subtract 90/40 from 5/42

1^st number: 5/42, 2^nd number: 2 10/40

5/42 - 90/40 is -179/84.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 40 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 42 × 20 = 840,
   5/42 = 5 × 20/42 × 20 = 100/840
3. Likewise, for the 2nd fraction, since 40 × 21 = 840,
   90/40 = 90 × 21/40 × 21 = 1890/840
4. Subtract the two like fractions:
   100/840 - 1890/840 = 100 - 1890/840 = -1790/840
5. After reducing the fraction, the answer is -179/84

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