Subtract 30/63 from 8/90, Solve 8/90

Subtract 30/63 from 8/90

8/90 - 30/63 is -122/315.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 63 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 90 × 7 = 630,
8/90 = 8 × 7/90 × 7 = 56/630
Likewise, for the 2nd fraction, since 63 × 10 = 630,
30/63 = 30 × 10/63 × 10 = 300/630
Subtract the two like fractions:
56/630 - 300/630 = 56 - 300/630 = -244/630
After reducing the fraction, the answer is -122/315

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