Subtract 21/70 from 84/9, Solve 9 3/9

Subtract 21/70 from 84/9

1^st number: 9 3/9, 2^nd number: 21/70

84/9 - 21/70 is 271/30.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 70 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 9 × 70 = 630,
84/9 = 84 × 70/9 × 70 = 5880/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630
Subtract the two like fractions:
5880/630 - 189/630 = 5880 - 189/630 = 5691/630
After reducing the fraction, the answer is 271/30
In mixed form: 91/30

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