Subtract 15/81 from 30/21
1st number: 1 9/21, 2nd number: 15/81
30/21 - 15/81 is 235/189.
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,
15/81 = 15 × 7/81 × 7 = 105/567 - Subtract the two like fractions:
810/567 - 105/567 = 810 - 105/567 = 705/567 - After reducing the fraction, the answer is 235/189
- In mixed form: 146/189
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