Subtract 21/63 from 9/30, Solve 9/30

Subtract 21/63 from 9/30

9/30 - 21/63 is -1/30.

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,
9/30 = 9 × 21/30 × 21 = 189/630
Likewise, for the 2nd fraction, since 63 × 10 = 630,
21/63 = 21 × 10/63 × 10 = 210/630
Subtract the two like fractions:
189/630 - 210/630 = 189 - 210/630 = -21/630
After reducing the fraction, the answer is -1/30

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