Subtract 6/9 from 81/21
1st number: 3 18/21, 2nd number: 6/9
81/21 - 6/9 is 67/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
81/21 = 81 × 3/21 × 3 = 243/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
6/9 = 6 × 7/9 × 7 = 42/63 - Subtract the two like fractions:
243/63 - 42/63 = 243 - 42/63 = 201/63 - After reducing the fraction, the answer is 67/21
- In mixed form: 34/21
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