Subtract 18/4 from 21/12
1st number: 1 9/12, 2nd number: 4 2/4
21/12 - 18/4 is -11/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 4 is 12
Next, find the equivalent fraction of both fractional numbers with denominator 12 - For the 1st fraction, since 12 × 1 = 12,
21/12 = 21 × 1/12 × 1 = 21/12 - Likewise, for the 2nd fraction, since 4 × 3 = 12,
18/4 = 18 × 3/4 × 3 = 54/12 - Subtract the two like fractions:
21/12 - 54/12 = 21 - 54/12 = -33/12 - After reducing the fraction, the answer is -11/4
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