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