Subtract 10/30 from 21/84
21/84 - 10/30 is -1/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 30 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 30 × 14 = 420,
10/30 = 10 × 14/30 × 14 = 140/420 - Subtract the two like fractions:
105/420 - 140/420 = 105 - 140/420 = -35/420 - After reducing the fraction, the answer is -1/12
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