Subtract 5/7 from 81/21
1st number: 3 18/21, 2nd number: 5/7
81/21 - 5/7 is 22/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
81/21 = 81 × 1/21 × 1 = 81/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
5/7 = 5 × 3/7 × 3 = 15/21 - Subtract the two like fractions:
81/21 - 15/21 = 81 - 15/21 = 66/21 - After reducing the fraction, the answer is 22/7
- In mixed form: 31/7
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