Subtract 30/21 from 63/9, Solve 7 0/9

Subtract 30/21 from 63/9

1^st number: 7 0/9, 2^nd number: 1 9/21

63/9 - 30/21 is 39/7.

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,
63/9 = 63 × 7/9 × 7 = 441/63
Likewise, for the 2nd fraction, since 21 × 3 = 63,
30/21 = 30 × 3/21 × 3 = 90/63
Subtract the two like fractions:
441/63 - 90/63 = 441 - 90/63 = 351/63
After reducing the fraction, the answer is 39/7
In mixed form: 54/7

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