Subtract 21/18 from 45/12
1st number: 3 9/12, 2nd number: 1 3/18
45/12 - 21/18 is 31/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 18 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 12 × 3 = 36,
45/12 = 45 × 3/12 × 3 = 135/36 - Likewise, for the 2nd fraction, since 18 × 2 = 36,
21/18 = 21 × 2/18 × 2 = 42/36 - Subtract the two like fractions:
135/36 - 42/36 = 135 - 42/36 = 93/36 - After reducing the fraction, the answer is 31/12
- In mixed form: 27/12
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