Subtract 6/28 from 81/21
1st number: 3 18/21, 2nd number: 6/28
81/21 - 6/28 is 51/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
81/21 = 81 × 4/21 × 4 = 324/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
6/28 = 6 × 3/28 × 3 = 18/84 - Subtract the two like fractions:
324/84 - 18/84 = 324 - 18/84 = 306/84 - After reducing the fraction, the answer is 51/14
- In mixed form: 39/14
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