Subtract 16/21 from 40/81
40/81 - 16/21 is -152/567.
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,
40/81 = 40 × 7/81 × 7 = 280/567 - Likewise, for the 2nd fraction, since 21 × 27 = 567,
16/21 = 16 × 27/21 × 27 = 432/567 - Subtract the two like fractions:
280/567 - 432/567 = 280 - 432/567 = -152/567
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