Subtract 42/81 from 72/21
1st number: 3 9/21, 2nd number: 42/81
72/21 - 42/81 is 550/189.
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,
72/21 = 72 × 27/21 × 27 = 1944/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
42/81 = 42 × 7/81 × 7 = 294/567 - Subtract the two like fractions:
1944/567 - 294/567 = 1944 - 294/567 = 1650/567 - After reducing the fraction, the answer is 550/189
- In mixed form: 2172/189
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