Subtract 21/35 from 3/12
3/12 - 21/35 is -7/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 35 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 12 × 35 = 420,
3/12 = 3 × 35/12 × 35 = 105/420 - Likewise, for the 2nd fraction, since 35 × 12 = 420,
21/35 = 21 × 12/35 × 12 = 252/420 - Subtract the two like fractions:
105/420 - 252/420 = 105 - 252/420 = -147/420 - After reducing the fraction, the answer is -7/20
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