Subtract 40/21 from 30/81
1st number: 30/81, 2nd number: 1 19/21
30/81 - 40/21 is -290/189.
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,
30/81 = 30 × 7/81 × 7 = 210/567 - Likewise, for the 2nd fraction, since 21 × 27 = 567,
40/21 = 40 × 27/21 × 27 = 1080/567 - Subtract the two like fractions:
210/567 - 1080/567 = 210 - 1080/567 = -870/567 - After reducing the fraction, the answer is -290/189
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