Subtract 28/18 from 21/2
1st number: 10 1/2, 2nd number: 1 10/18
21/2 - 28/18 is 161/18.
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,
21/2 = 21 × 9/2 × 9 = 189/18 - Likewise, for the 2nd fraction, since 18 × 1 = 18,
28/18 = 28 × 1/18 × 1 = 28/18 - Subtract the two like fractions:
189/18 - 28/18 = 189 - 28/18 = 161/18 - In mixed form: 817/18
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