Subtract 30/18 from 21/98, Solve 21/98

Subtract 30/18 from 21/98

1^st number: 21/98, 2^nd number: 1 12/18

21/98 - 30/18 is -61/42.

Find the least common denominator or LCM of the two denominators:
LCM of 98 and 18 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 18 × 49 = 882,
30/18 = 30 × 49/18 × 49 = 1470/882
Subtract the two like fractions:
189/882 - 1470/882 = 189 - 1470/882 = -1281/882
After reducing the fraction, the answer is -61/42

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