Subtract 21/4 from 12/42
1st number: 12/42, 2nd number: 5 1/4
12/42 - 21/4 is -139/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 4 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
12/42 = 12 × 2/42 × 2 = 24/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
21/4 = 21 × 21/4 × 21 = 441/84 - Subtract the two like fractions:
24/84 - 441/84 = 24 - 441/84 = -417/84 - After reducing the fraction, the answer is -139/28
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