Subtract 90/9 from 21/98, Solve 21/98

Subtract 90/9 from 21/98

1^st number: 21/98, 2^nd number: 10 0/9

21/98 - 90/9 is -137/14.

Find the least common denominator or LCM of the two denominators:
LCM of 98 and 9 is 882

Next, find the equivalent fraction of both fractional numbers with denominator 882
For the 1st fraction, since 98 × 9 = 882,
21/98 = 21 × 9/98 × 9 = 189/882
Likewise, for the 2nd fraction, since 9 × 98 = 882,
90/9 = 90 × 98/9 × 98 = 8820/882
Subtract the two like fractions:
189/882 - 8820/882 = 189 - 8820/882 = -8631/882
After reducing the fraction, the answer is -137/14

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