Subtract 42/80 from 30/98, Solve 30/98

Subtract 42/80 from 30/98

30/98 - 42/80 is -429/1960.

Find the least common denominator or LCM of the two denominators:
LCM of 98 and 80 is 3920

Next, find the equivalent fraction of both fractional numbers with denominator 3920
For the 1st fraction, since 98 × 40 = 3920,
30/98 = 30 × 40/98 × 40 = 1200/3920
Likewise, for the 2nd fraction, since 80 × 49 = 3920,
42/80 = 42 × 49/80 × 49 = 2058/3920
Subtract the two like fractions:
1200/3920 - 2058/3920 = 1200 - 2058/3920 = -858/3920
After reducing the fraction, the answer is -429/1960

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