Subtract 42/12 from 21/3
1st number: 7 0/3, 2nd number: 3 6/12
21/3 - 42/12 is 7/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 12 is 12
Next, find the equivalent fraction of both fractional numbers with denominator 12 - For the 1st fraction, since 3 × 4 = 12,
21/3 = 21 × 4/3 × 4 = 84/12 - Likewise, for the 2nd fraction, since 12 × 1 = 12,
42/12 = 42 × 1/12 × 1 = 42/12 - Subtract the two like fractions:
84/12 - 42/12 = 84 - 42/12 = 42/12 - After reducing the fraction, the answer is 7/2
- In mixed form: 31/2
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