Subtract 30/4 from 21/98, Solve 21/98

Subtract 30/4 from 21/98

1^st number: 21/98, 2^nd number: 7 2/4

21/98 - 30/4 is -51/7.

Find the least common denominator or LCM of the two denominators:
LCM of 98 and 4 is 196

Next, find the equivalent fraction of both fractional numbers with denominator 196
For the 1st fraction, since 98 × 2 = 196,
21/98 = 21 × 2/98 × 2 = 42/196
Likewise, for the 2nd fraction, since 4 × 49 = 196,
30/4 = 30 × 49/4 × 49 = 1470/196
Subtract the two like fractions:
42/196 - 1470/196 = 42 - 1470/196 = -1428/196
After reducing the fraction, the answer is -51/7

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