Subtract 21/12 from 72/9
1st number: 8 0/9, 2nd number: 1 9/12
72/9 - 21/12 is 25/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 12 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 9 × 4 = 36,
72/9 = 72 × 4/9 × 4 = 288/36 - Likewise, for the 2nd fraction, since 12 × 3 = 36,
21/12 = 21 × 3/12 × 3 = 63/36 - Subtract the two like fractions:
288/36 - 63/36 = 288 - 63/36 = 225/36 - After reducing the fraction, the answer is 25/4
- In mixed form: 61/4
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