Answers

Subtract 21/42 from 6/8

6/8 - 21/42 is 1/4.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 8 and 42 is 168
   
   Next, find the equivalent fraction of both fractional numbers with denominator 168
2. For the 1st fraction, since 8 × 21 = 168,
   6/8 = 6 × 21/8 × 21 = 126/168
3. Likewise, for the 2nd fraction, since 42 × 4 = 168,
   21/42 = 21 × 4/42 × 4 = 84/168
4. Subtract the two like fractions:
   126/168 - 84/168 = 126 - 84/168 = 42/168
5. After reducing the fraction, the answer is 1/4

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