Subtract 20/21 from 81/3
1st number: 27 0/3, 2nd number: 20/21
81/3 - 20/21 is 547/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 21 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 3 × 7 = 21,
81/3 = 81 × 7/3 × 7 = 567/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
20/21 = 20 × 1/21 × 1 = 20/21 - Subtract the two like fractions:
567/21 - 20/21 = 567 - 20/21 = 547/21 - In mixed form: 261/21
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