Subtract 18/12 from 21/36
1st number: 21/36, 2nd number: 1 6/12
21/36 - 18/12 is -11/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 12 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 36 × 1 = 36,
21/36 = 21 × 1/36 × 1 = 21/36 - Likewise, for the 2nd fraction, since 12 × 3 = 36,
18/12 = 18 × 3/12 × 3 = 54/36 - Subtract the two like fractions:
21/36 - 54/36 = 21 - 54/36 = -33/36 - After reducing the fraction, the answer is -11/12
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