Subtract 80/63 from 28/30, Solve 28/30

Subtract 80/63 from 28/30

1^st number: 28/30, 2^nd number: 1 17/63

28/30 - 80/63 is -106/315.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 63 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 30 × 21 = 630,
28/30 = 28 × 21/30 × 21 = 588/630
Likewise, for the 2nd fraction, since 63 × 10 = 630,
80/63 = 80 × 10/63 × 10 = 800/630
Subtract the two like fractions:
588/630 - 800/630 = 588 - 800/630 = -212/630
After reducing the fraction, the answer is -106/315

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