Subtract 21/27 from 84/18, Solve 4 12/18

Subtract 21/27 from 84/18

1^st number: 4 12/18, 2^nd number: 21/27

84/18 - 21/27 is 35/9.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 27 is 54

Next, find the equivalent fraction of both fractional numbers with denominator 54
For the 1st fraction, since 18 × 3 = 54,
84/18 = 84 × 3/18 × 3 = 252/54
Likewise, for the 2nd fraction, since 27 × 2 = 54,
21/27 = 21 × 2/27 × 2 = 42/54
Subtract the two like fractions:
252/54 - 42/54 = 252 - 42/54 = 210/54
After reducing the fraction, the answer is 35/9
In mixed form: 38/9

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