Subtract 80/98 from 42/70, Solve 42/70

Subtract 80/98 from 42/70

42/70 - 80/98 is -53/245.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 98 is 490

Next, find the equivalent fraction of both fractional numbers with denominator 490
For the 1st fraction, since 70 × 7 = 490,
42/70 = 42 × 7/70 × 7 = 294/490
Likewise, for the 2nd fraction, since 98 × 5 = 490,
80/98 = 80 × 5/98 × 5 = 400/490
Subtract the two like fractions:
294/490 - 400/490 = 294 - 400/490 = -106/490
After reducing the fraction, the answer is -53/245

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