Subtract 81/18 from 9/21
1st number: 9/21, 2nd number: 4 9/18
9/21 - 81/18 is -57/14.
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,
9/21 = 9 × 6/21 × 6 = 54/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
81/18 = 81 × 7/18 × 7 = 567/126 - Subtract the two like fractions:
54/126 - 567/126 = 54 - 567/126 = -513/126 - After reducing the fraction, the answer is -57/14
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