Subtract 49/70 from 21/49
21/49 - 49/70 is -19/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 70 is 490
Next, find the equivalent fraction of both fractional numbers with denominator 490 - For the 1st fraction, since 49 × 10 = 490,
21/49 = 21 × 10/49 × 10 = 210/490 - Likewise, for the 2nd fraction, since 70 × 7 = 490,
49/70 = 49 × 7/70 × 7 = 343/490 - Subtract the two like fractions:
210/490 - 343/490 = 210 - 343/490 = -133/490 - After reducing the fraction, the answer is -19/70
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