Subtract 21/18 from 6/9
1st number: 6/9, 2nd number: 1 3/18
6/9 - 21/18 is -1/2.
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,
6/9 = 6 × 2/9 × 2 = 12/18 - Likewise, for the 2nd fraction, since 18 × 1 = 18,
21/18 = 21 × 1/18 × 1 = 21/18 - Subtract the two like fractions:
12/18 - 21/18 = 12 - 21/18 = -9/18 - After reducing the fraction, the answer is -1/2
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