Subtract 18/9 from 21/12
1st number: 1 9/12, 2nd number: 2 0/9
21/12 - 18/9 is -1/4.
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,
21/12 = 21 × 3/12 × 3 = 63/36 - Likewise, for the 2nd fraction, since 9 × 4 = 36,
18/9 = 18 × 4/9 × 4 = 72/36 - Subtract the two like fractions:
63/36 - 72/36 = 63 - 72/36 = -9/36 - After reducing the fraction, the answer is -1/4
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