Answers

Subtract 8/40 from 15/42

15/42 - 8/40 is 11/70.

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,
   8/40 = 8 × 21/40 × 21 = 168/840
4. Subtract the two like fractions:
   300/840 - 168/840 = 300 - 168/840 = 132/840
5. After reducing the fraction, the answer is 11/70

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