Subtract 25/21 from 30/9, Solve 3 3/9

Subtract 25/21 from 30/9

1^st number: 3 3/9, 2^nd number: 1 4/21

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

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,
30/9 = 30 × 7/9 × 7 = 210/63
Likewise, for the 2nd fraction, since 21 × 3 = 63,
25/21 = 25 × 3/21 × 3 = 75/63
Subtract the two like fractions:
210/63 - 75/63 = 210 - 75/63 = 135/63
After reducing the fraction, the answer is 15/7
In mixed form: 21/7

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