Answers

Subtract 56/40 from 15/42

1^st number: 15/42, 2^nd number: 1 16/40

15/42 - 56/40 is -73/70.

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,
   15/42 = 15 × 20/42 × 20 = 300/840
3. Likewise, for the 2nd fraction, since 40 × 21 = 840,
   56/40 = 56 × 21/40 × 21 = 1176/840
4. Subtract the two like fractions:
   300/840 - 1176/840 = 300 - 1176/840 = -876/840
5. After reducing the fraction, the answer is -73/70

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