Subtract 3/21 from 21/9, Solve 2 3/9

Subtract 3/21 from 21/9

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

21/9 - 3/21 is 46/21.

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

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 9 × 7 = 63,
21/9 = 21 × 7/9 × 7 = 147/63
Likewise, for the 2nd fraction, since 21 × 3 = 63,
3/21 = 3 × 3/21 × 3 = 9/63
Subtract the two like fractions:
147/63 - 9/63 = 147 - 9/63 = 138/63
After reducing the fraction, the answer is 46/21
In mixed form: 24/21

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