Subtract 18/81 from 72/42
1st number: 1 30/42, 2nd number: 18/81
72/42 - 18/81 is 94/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 81 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 42 × 27 = 1134,
72/42 = 72 × 27/42 × 27 = 1944/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
18/81 = 18 × 14/81 × 14 = 252/1134 - Subtract the two like fractions:
1944/1134 - 252/1134 = 1944 - 252/1134 = 1692/1134 - After reducing the fraction, the answer is 94/63
- In mixed form: 131/63
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