Subtract 21/81 from 30/21
1st number: 1 9/21, 2nd number: 21/81
30/21 - 21/81 is 221/189.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
30/21 = 30 × 27/21 × 27 = 810/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
21/81 = 21 × 7/81 × 7 = 147/567 - Subtract the two like fractions:
810/567 - 147/567 = 810 - 147/567 = 663/567 - After reducing the fraction, the answer is 221/189
- In mixed form: 132/189
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