Subtract 12/21 from 9/4, Solve 2 1/4

Subtract 12/21 from 9/4

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

9/4 - 12/21 is 47/28.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 4 × 21 = 84,
9/4 = 9 × 21/4 × 21 = 189/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
12/21 = 12 × 4/21 × 4 = 48/84
Subtract the two like fractions:
189/84 - 48/84 = 189 - 48/84 = 141/84
After reducing the fraction, the answer is 47/28
In mixed form: 119/28

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