Subtract 5/21 from 18/9, Solve 2 0/9

Subtract 5/21 from 18/9

1^st number: 2 0/9, 2^nd number: 5/21

18/9 - 5/21 is 37/21.

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,
18/9 = 18 × 7/9 × 7 = 126/63
Likewise, for the 2nd fraction, since 21 × 3 = 63,
5/21 = 5 × 3/21 × 3 = 15/63
Subtract the two like fractions:
126/63 - 15/63 = 126 - 15/63 = 111/63
After reducing the fraction, the answer is 37/21
In mixed form: 116/21

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