Subtract 7/21 from 1/18
1/18 - 7/21 is -5/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
1/18 = 1 × 7/18 × 7 = 7/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
7/21 = 7 × 6/21 × 6 = 42/126 - Subtract the two like fractions:
7/126 - 42/126 = 7 - 42/126 = -35/126 - After reducing the fraction, the answer is -5/18
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