Subtract 21/49 from 70/84
70/84 - 21/49 is 17/42.
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,
70/84 = 70 × 7/84 × 7 = 490/588 - Likewise, for the 2nd fraction, since 49 × 12 = 588,
21/49 = 21 × 12/49 × 12 = 252/588 - Subtract the two like fractions:
490/588 - 252/588 = 490 - 252/588 = 238/588 - After reducing the fraction, the answer is 17/42
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