Answers

Subtract 4/18 from 4/21

4/21 - 4/18 is -2/63.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 18 is 126
   
   Next, find the equivalent fraction of both fractional numbers with denominator 126
2. For the 1st fraction, since 21 × 6 = 126,
   4/21 = 4 × 6/21 × 6 = 24/126
3. Likewise, for the 2nd fraction, since 18 × 7 = 126,
   4/18 = 4 × 7/18 × 7 = 28/126
4. Subtract the two like fractions:
   24/126 - 28/126 = 24 - 28/126 = -4/126
5. After reducing the fraction, the answer is -2/63

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