Subtract 21/18 from 12/9
1st number: 1 3/9, 2nd number: 1 3/18
12/9 - 21/18 is 1/6.
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,
12/9 = 12 × 2/9 × 2 = 24/18 - Likewise, for the 2nd fraction, since 18 × 1 = 18,
21/18 = 21 × 1/18 × 1 = 21/18 - Subtract the two like fractions:
24/18 - 21/18 = 24 - 21/18 = 3/18 - After reducing the fraction, the answer is 1/6
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