Subtract 20/84 from 30/9, Solve 3 3/9

Subtract 20/84 from 30/9

1^st number: 3 3/9, 2^nd number: 20/84

30/9 - 20/84 is 65/21.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 84 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 9 × 28 = 252,
30/9 = 30 × 28/9 × 28 = 840/252
Likewise, for the 2nd fraction, since 84 × 3 = 252,
20/84 = 20 × 3/84 × 3 = 60/252
Subtract the two like fractions:
840/252 - 60/252 = 840 - 60/252 = 780/252
After reducing the fraction, the answer is 65/21
In mixed form: 32/21

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