Subtract 7/15 from 21/9, Solve 2 3/9

Subtract 7/15 from 21/9

1^st number: 2 3/9, 2^nd number: 7/15

21/9 - 7/15 is 28/15.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 15 is 45

Next, find the equivalent fraction of both fractional numbers with denominator 45
For the 1st fraction, since 9 × 5 = 45,
21/9 = 21 × 5/9 × 5 = 105/45
Likewise, for the 2nd fraction, since 15 × 3 = 45,
7/15 = 7 × 3/15 × 3 = 21/45
Subtract the two like fractions:
105/45 - 21/45 = 105 - 21/45 = 84/45
After reducing the fraction, the answer is 28/15
In mixed form: 113/15

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