Subtract 9/21 from 63/18, Solve 3 9/18

Subtract 9/21 from 63/18

1^st number: 3 9/18, 2^nd number: 9/21

63/18 - 9/21 is 43/14.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
63/18 = 63 × 7/18 × 7 = 441/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
9/21 = 9 × 6/21 × 6 = 54/126
Subtract the two like fractions:
441/126 - 54/126 = 441 - 54/126 = 387/126
After reducing the fraction, the answer is 43/14
In mixed form: 31/14

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