Subtract 21/9 from 42/12
1st number: 3 6/12, 2nd number: 2 3/9
42/12 - 21/9 is 7/6.
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,
42/12 = 42 × 3/12 × 3 = 126/36 - Likewise, for the 2nd fraction, since 9 × 4 = 36,
21/9 = 21 × 4/9 × 4 = 84/36 - Subtract the two like fractions:
126/36 - 84/36 = 126 - 84/36 = 42/36 - After reducing the fraction, the answer is 7/6
- In mixed form: 11/6
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