Subtract 54/70 from 21/49
21/49 - 54/70 is -12/35.
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,
54/70 = 54 × 7/70 × 7 = 378/490 - Subtract the two like fractions:
210/490 - 378/490 = 210 - 378/490 = -168/490 - After reducing the fraction, the answer is -12/35
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