Subtract 2/98 from 21/90, Solve 21/90

Subtract 2/98 from 21/90

21/90 - 2/98 is 313/1470.

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

Next, find the equivalent fraction of both fractional numbers with denominator 4410
For the 1st fraction, since 90 × 49 = 4410,
21/90 = 21 × 49/90 × 49 = 1029/4410
Likewise, for the 2nd fraction, since 98 × 45 = 4410,
2/98 = 2 × 45/98 × 45 = 90/4410
Subtract the two like fractions:
1029/4410 - 90/4410 = 1029 - 90/4410 = 939/4410
After reducing the fraction, the answer is 313/1470

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