Subtract 27/12 from 75/21, Solve 3 12/21

Subtract 27/12 from 75/21

1^st number: 3 12/21, 2^nd number: 2 3/12

75/21 - 27/12 is 37/28.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
75/21 = 75 × 4/21 × 4 = 300/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
27/12 = 27 × 7/12 × 7 = 189/84
Subtract the two like fractions:
300/84 - 189/84 = 300 - 189/84 = 111/84
After reducing the fraction, the answer is 37/28
In mixed form: 19/28

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