Subtract 20/21 from 81/9
1st number: 9 0/9, 2nd number: 20/21
81/9 - 20/21 is 169/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 9 × 7 = 63,
81/9 = 81 × 7/9 × 7 = 567/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
20/21 = 20 × 3/21 × 3 = 60/63 - Subtract the two like fractions:
567/63 - 60/63 = 567 - 60/63 = 507/63 - After reducing the fraction, the answer is 169/21
- In mixed form: 81/21
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