Subtract 12/9 from 81/7
1st number: 11 4/7, 2nd number: 1 3/9
81/7 - 12/9 is 215/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 7 × 9 = 63,
81/7 = 81 × 9/7 × 9 = 729/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
12/9 = 12 × 7/9 × 7 = 84/63 - Subtract the two like fractions:
729/63 - 84/63 = 729 - 84/63 = 645/63 - After reducing the fraction, the answer is 215/21
- In mixed form: 105/21
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