Subtract 21/9 from 3/12
1st number: 3/12, 2nd number: 2 3/9
3/12 - 21/9 is -25/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 9 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 12 × 3 = 36,
3/12 = 3 × 3/12 × 3 = 9/36 - Likewise, for the 2nd fraction, since 9 × 4 = 36,
21/9 = 21 × 4/9 × 4 = 84/36 - Subtract the two like fractions:
9/36 - 84/36 = 9 - 84/36 = -75/36 - After reducing the fraction, the answer is -25/12
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