Subtract 56/90 from 6/21, Solve 6/21

Subtract 56/90 from 6/21

6/21 - 56/90 is -106/315.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 21 × 30 = 630,
6/21 = 6 × 30/21 × 30 = 180/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
56/90 = 56 × 7/90 × 7 = 392/630
Subtract the two like fractions:
180/630 - 392/630 = 180 - 392/630 = -212/630
After reducing the fraction, the answer is -106/315

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