Subtract 81/18 from 18/84
1st number: 18/84, 2nd number: 4 9/18
18/84 - 81/18 is -30/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 18 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 84 × 3 = 252,
18/84 = 18 × 3/84 × 3 = 54/252 - Likewise, for the 2nd fraction, since 18 × 14 = 252,
81/18 = 81 × 14/18 × 14 = 1134/252 - Subtract the two like fractions:
54/252 - 1134/252 = 54 - 1134/252 = -1080/252 - After reducing the fraction, the answer is -30/7
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