Subtract 6/18 from 3/21
3/21 - 6/18 is -4/21.
Steps for subtracting fractions
- 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 - For the 1st fraction, since 21 × 6 = 126,
3/21 = 3 × 6/21 × 6 = 18/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
6/18 = 6 × 7/18 × 7 = 42/126 - Subtract the two like fractions:
18/126 - 42/126 = 18 - 42/126 = -24/126 - After reducing the fraction, the answer is -4/21
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