Subtract 9/21 from 7/18
7/18 - 9/21 is -5/126.
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,
7/18 = 7 × 7/18 × 7 = 49/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
9/21 = 9 × 6/21 × 6 = 54/126 - Subtract the two like fractions:
49/126 - 54/126 = 49 - 54/126 = -5/126
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