Subtract 15/12 from 21/6
1st number: 3 3/6, 2nd number: 1 3/12
21/6 - 15/12 is 9/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 6 and 12 is 12
Next, find the equivalent fraction of both fractional numbers with denominator 12 - For the 1st fraction, since 6 × 2 = 12,
21/6 = 21 × 2/6 × 2 = 42/12 - Likewise, for the 2nd fraction, since 12 × 1 = 12,
15/12 = 15 × 1/12 × 1 = 15/12 - Subtract the two like fractions:
42/12 - 15/12 = 42 - 15/12 = 27/12 - After reducing the fraction, the answer is 9/4
- In mixed form: 21/4
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