Subtract 42/98 from 1/21, Solve 1/21

Subtract 42/98 from 1/21

1/21 - 42/98 is -8/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 98 is 294

Next, find the equivalent fraction of both fractional numbers with denominator 294
For the 1st fraction, since 21 × 14 = 294,
1/21 = 1 × 14/21 × 14 = 14/294
Likewise, for the 2nd fraction, since 98 × 3 = 294,
42/98 = 42 × 3/98 × 3 = 126/294
Subtract the two like fractions:
14/294 - 126/294 = 14 - 126/294 = -112/294
After reducing the fraction, the answer is -8/21

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