Subtract 28/49 from 21/84
21/84 - 28/49 is -9/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 49 is 588
Next, find the equivalent fraction of both fractional numbers with denominator 588 - For the 1st fraction, since 84 × 7 = 588,
21/84 = 21 × 7/84 × 7 = 147/588 - Likewise, for the 2nd fraction, since 49 × 12 = 588,
28/49 = 28 × 12/49 × 12 = 336/588 - Subtract the two like fractions:
147/588 - 336/588 = 147 - 336/588 = -189/588 - After reducing the fraction, the answer is -9/28
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