Subtract 21/18 from 8/81
1st number: 8/81, 2nd number: 1 3/18
8/81 - 21/18 is -173/162.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 18 is 162
Next, find the equivalent fraction of both fractional numbers with denominator 162 - For the 1st fraction, since 81 × 2 = 162,
8/81 = 8 × 2/81 × 2 = 16/162 - Likewise, for the 2nd fraction, since 18 × 9 = 162,
21/18 = 21 × 9/18 × 9 = 189/162 - Subtract the two like fractions:
16/162 - 189/162 = 16 - 189/162 = -173/162
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