Subtract 81/12 from 45/18
1st number: 2 9/18, 2nd number: 6 9/12
45/18 - 81/12 is -17/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 12 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 18 × 2 = 36,
45/18 = 45 × 2/18 × 2 = 90/36 - Likewise, for the 2nd fraction, since 12 × 3 = 36,
81/12 = 81 × 3/12 × 3 = 243/36 - Subtract the two like fractions:
90/36 - 243/36 = 90 - 243/36 = -153/36 - After reducing the fraction, the answer is -17/4
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