Subtract 42/98 from 21/90
21/90 - 42/98 is -41/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 98 is 4410
Next, find the equivalent fraction of both fractional numbers with denominator 4410 - For the 1st fraction, since 90 × 49 = 4410,
21/90 = 21 × 49/90 × 49 = 1029/4410 - Likewise, for the 2nd fraction, since 98 × 45 = 4410,
42/98 = 42 × 45/98 × 45 = 1890/4410 - Subtract the two like fractions:
1029/4410 - 1890/4410 = 1029 - 1890/4410 = -861/4410 - After reducing the fraction, the answer is -41/210
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