Subtract 4/12 from 8/21
8/21 - 4/12 is 1/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
8/21 = 8 × 4/21 × 4 = 32/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
4/12 = 4 × 7/12 × 7 = 28/84 - Subtract the two like fractions:
32/84 - 28/84 = 32 - 28/84 = 4/84 - After reducing the fraction, the answer is 1/21
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