Subtract 81/72 from 30/12
1st number: 2 6/12, 2nd number: 1 9/72
30/12 - 81/72 is 11/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 12 × 6 = 72,
30/12 = 30 × 6/12 × 6 = 180/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
81/72 = 81 × 1/72 × 1 = 81/72 - Subtract the two like fractions:
180/72 - 81/72 = 180 - 81/72 = 99/72 - After reducing the fraction, the answer is 11/8
- In mixed form: 13/8
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