Subtract 42/70 from 21/98
21/98 - 42/70 is -27/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 98 and 70 is 490
Next, find the equivalent fraction of both fractional numbers with denominator 490 - For the 1st fraction, since 98 × 5 = 490,
21/98 = 21 × 5/98 × 5 = 105/490 - Likewise, for the 2nd fraction, since 70 × 7 = 490,
42/70 = 42 × 7/70 × 7 = 294/490 - Subtract the two like fractions:
105/490 - 294/490 = 105 - 294/490 = -189/490 - After reducing the fraction, the answer is -27/70
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