Subtract 9/63 from 84/21, Solve 4 0/21

Subtract 9/63 from 84/21

1^st number: 4 0/21, 2^nd number: 9/63

84/21 - 9/63 is 27/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 21 × 3 = 63,
84/21 = 84 × 3/21 × 3 = 252/63
Likewise, for the 2nd fraction, since 63 × 1 = 63,
9/63 = 9 × 1/63 × 1 = 9/63
Subtract the two like fractions:
252/63 - 9/63 = 252 - 9/63 = 243/63
After reducing the fraction, the answer is 27/7
In mixed form: 36/7

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