Subtract 81/84 from 7/18
7/18 - 81/84 is -145/252.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 84 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 18 × 14 = 252,
7/18 = 7 × 14/18 × 14 = 98/252 - Likewise, for the 2nd fraction, since 84 × 3 = 252,
81/84 = 81 × 3/84 × 3 = 243/252 - Subtract the two like fractions:
98/252 - 243/252 = 98 - 243/252 = -145/252
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