Subtract 15/7 from 30/9, Solve 3 3/9

Subtract 15/7 from 30/9

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

30/9 - 15/7 is 25/21.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 7 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 9 × 7 = 63,
30/9 = 30 × 7/9 × 7 = 210/63
Likewise, for the 2nd fraction, since 7 × 9 = 63,
15/7 = 15 × 9/7 × 9 = 135/63
Subtract the two like fractions:
210/63 - 135/63 = 210 - 135/63 = 75/63
After reducing the fraction, the answer is 25/21
In mixed form: 14/21

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