Subtract 21/81 from 84/42
1st number: 2 0/42, 2nd number: 21/81
84/42 - 21/81 is 47/27.
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,
84/42 = 84 × 27/42 × 27 = 2268/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
21/81 = 21 × 14/81 × 14 = 294/1134 - Subtract the two like fractions:
2268/1134 - 294/1134 = 2268 - 294/1134 = 1974/1134 - After reducing the fraction, the answer is 47/27
- In mixed form: 120/27
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