Subtract 90/81 from 21/98
1st number: 21/98, 2nd number: 1 9/81
21/98 - 90/81 is -113/126.
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,
21/98 = 21 × 81/98 × 81 = 1701/7938 - Likewise, for the 2nd fraction, since 81 × 98 = 7938,
90/81 = 90 × 98/81 × 98 = 8820/7938 - Subtract the two like fractions:
1701/7938 - 8820/7938 = 1701 - 8820/7938 = -7119/7938 - After reducing the fraction, the answer is -113/126
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