Subtract 8/21 from 28/81
28/81 - 8/21 is -20/567.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 21 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
28/81 = 28 × 7/81 × 7 = 196/567 - Likewise, for the 2nd fraction, since 21 × 27 = 567,
8/21 = 8 × 27/21 × 27 = 216/567 - Subtract the two like fractions:
196/567 - 216/567 = 196 - 216/567 = -20/567
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