Subtract 20/18 from 21/9
1st number: 2 3/9, 2nd number: 1 2/18
21/9 - 20/18 is 11/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 18 is 18
Next, find the equivalent fraction of both fractional numbers with denominator 18 - For the 1st fraction, since 9 × 2 = 18,
21/9 = 21 × 2/9 × 2 = 42/18 - Likewise, for the 2nd fraction, since 18 × 1 = 18,
20/18 = 20 × 1/18 × 1 = 20/18 - Subtract the two like fractions:
42/18 - 20/18 = 42 - 20/18 = 22/18 - After reducing the fraction, the answer is 11/9
- In mixed form: 12/9
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