Subtract 21/81 from 7/98
7/98 - 21/81 is -71/378.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 98 and 81 is 7938
Next, find the equivalent fraction of both fractional numbers with denominator 7938 - For the 1st fraction, since 98 × 81 = 7938,
7/98 = 7 × 81/98 × 81 = 567/7938 - Likewise, for the 2nd fraction, since 81 × 98 = 7938,
21/81 = 21 × 98/81 × 98 = 2058/7938 - Subtract the two like fractions:
567/7938 - 2058/7938 = 567 - 2058/7938 = -1491/7938 - After reducing the fraction, the answer is -71/378
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