Answers

Subtract 7/8 from 42/20

1^st number: 2 2/20, 2^nd number: 7/8

42/20 - 7/8 is 49/40.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 8 is 40
   
   Next, find the equivalent fraction of both fractional numbers with denominator 40
2. For the 1st fraction, since 20 × 2 = 40,
   42/20 = 42 × 2/20 × 2 = 84/40
3. Likewise, for the 2nd fraction, since 8 × 5 = 40,
   7/8 = 7 × 5/8 × 5 = 35/40
4. Subtract the two like fractions:
   84/40 - 35/40 = 84 - 35/40 = 49/40
5. In mixed form: 19/40

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