Subtract 72/81 from 28/7
1st number: 4 0/7, 2nd number: 72/81
28/7 - 72/81 is 28/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 7 × 81 = 567,
28/7 = 28 × 81/7 × 81 = 2268/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
72/81 = 72 × 7/81 × 7 = 504/567 - Subtract the two like fractions:
2268/567 - 504/567 = 2268 - 504/567 = 1764/567 - After reducing the fraction, the answer is 28/9
- In mixed form: 31/9
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