Subtract 70/90 from 7/98, Solve 7/98

Subtract 70/90 from 7/98

7/98 - 70/90 is -89/126.

Find the least common denominator or LCM of the two denominators:
LCM of 98 and 90 is 4410

Next, find the equivalent fraction of both fractional numbers with denominator 4410
For the 1st fraction, since 98 × 45 = 4410,
7/98 = 7 × 45/98 × 45 = 315/4410
Likewise, for the 2nd fraction, since 90 × 49 = 4410,
70/90 = 70 × 49/90 × 49 = 3430/4410
Subtract the two like fractions:
315/4410 - 3430/4410 = 315 - 3430/4410 = -3115/4410
After reducing the fraction, the answer is -89/126

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