Subtract 12/6 from 21/42
1st number: 21/42, 2nd number: 2 0/6
21/42 - 12/6 is -3/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 6 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
21/42 = 21 × 1/42 × 1 = 21/42 - Likewise, for the 2nd fraction, since 6 × 7 = 42,
12/6 = 12 × 7/6 × 7 = 84/42 - Subtract the two like fractions:
21/42 - 84/42 = 21 - 84/42 = -63/42 - After reducing the fraction, the answer is -3/2
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