Subtract 20/21 from 28/12, Solve 2 4/12

Subtract 20/21 from 28/12

1^st number: 2 4/12, 2^nd number: 20/21

28/12 - 20/21 is 29/21.

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

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
28/12 = 28 × 7/12 × 7 = 196/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84
Subtract the two like fractions:
196/84 - 80/84 = 196 - 80/84 = 116/84
After reducing the fraction, the answer is 29/21
In mixed form: 18/21

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