Subtract 3/9 from 72/21, Solve 3 9/21

Subtract 3/9 from 72/21

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

72/21 - 3/9 is 65/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 21 × 3 = 63,
72/21 = 72 × 3/21 × 3 = 216/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
3/9 = 3 × 7/9 × 7 = 21/63
Subtract the two like fractions:
216/63 - 21/63 = 216 - 21/63 = 195/63
After reducing the fraction, the answer is 65/21
In mixed form: 32/21

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