Answers

Subtract 21/8 from 42/4

1^st number: 10 2/4, 2^nd number: 2 5/8

42/4 - 21/8 is 63/8.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 4 and 8 is 8
   
   Next, find the equivalent fraction of both fractional numbers with denominator 8
2. For the 1st fraction, since 4 × 2 = 8,
   42/4 = 42 × 2/4 × 2 = 84/8
3. Likewise, for the 2nd fraction, since 8 × 1 = 8,
   21/8 = 21 × 1/8 × 1 = 21/8
4. Subtract the two like fractions:
   84/8 - 21/8 = 84 - 21/8 = 63/8
5. In mixed form: 77/8

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