Answers

Subtract 21/42 from 8/36

8/36 - 21/42 is -5/18.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 36 and 42 is 252
   
   Next, find the equivalent fraction of both fractional numbers with denominator 252
2. For the 1st fraction, since 36 × 7 = 252,
   8/36 = 8 × 7/36 × 7 = 56/252
3. Likewise, for the 2nd fraction, since 42 × 6 = 252,
   21/42 = 21 × 6/42 × 6 = 126/252
4. Subtract the two like fractions:
   56/252 - 126/252 = 56 - 126/252 = -70/252
5. After reducing the fraction, the answer is -5/18

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