Subtract 18/9 from 21/2
1st number: 10 1/2, 2nd number: 2 0/9
21/2 - 18/9 is 17/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 9 is 18
Next, find the equivalent fraction of both fractional numbers with denominator 18 - For the 1st fraction, since 2 × 9 = 18,
21/2 = 21 × 9/2 × 9 = 189/18 - Likewise, for the 2nd fraction, since 9 × 2 = 18,
18/9 = 18 × 2/9 × 2 = 36/18 - Subtract the two like fractions:
189/18 - 36/18 = 189 - 36/18 = 153/18 - After reducing the fraction, the answer is 17/2
- In mixed form: 81/2
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