Subtract 81/21 from 45/12
1st number: 3 9/12, 2nd number: 3 18/21
45/12 - 81/21 is -3/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
45/12 = 45 × 7/12 × 7 = 315/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
81/21 = 81 × 4/21 × 4 = 324/84 - Subtract the two like fractions:
315/84 - 324/84 = 315 - 324/84 = -9/84 - After reducing the fraction, the answer is -3/28
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