Answers

Subtract 42/8 from 21/40

1^st number: 21/40, 2^nd number: 5 2/8

21/40 - 42/8 is -189/40.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 8 is 40
   
   Next, find the equivalent fraction of both fractional numbers with denominator 40
2. For the 1st fraction, since 40 × 1 = 40,
   21/40 = 21 × 1/40 × 1 = 21/40
3. Likewise, for the 2nd fraction, since 8 × 5 = 40,
   42/8 = 42 × 5/8 × 5 = 210/40
4. Subtract the two like fractions:
   21/40 - 210/40 = 21 - 210/40 = -189/40

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