Subtract 21/70 from 12/49
12/49 - 21/70 is -27/490.
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,
12/49 = 12 × 10/49 × 10 = 120/490 - Likewise, for the 2nd fraction, since 70 × 7 = 490,
21/70 = 21 × 7/70 × 7 = 147/490 - Subtract the two like fractions:
120/490 - 147/490 = 120 - 147/490 = -27/490
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