Subtract 42/81 from 21/2
1st number: 10 1/2, 2nd number: 42/81
21/2 - 42/81 is 539/54.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 81 is 162
Next, find the equivalent fraction of both fractional numbers with denominator 162 - For the 1st fraction, since 2 × 81 = 162,
21/2 = 21 × 81/2 × 81 = 1701/162 - Likewise, for the 2nd fraction, since 81 × 2 = 162,
42/81 = 42 × 2/81 × 2 = 84/162 - Subtract the two like fractions:
1701/162 - 84/162 = 1701 - 84/162 = 1617/162 - After reducing the fraction, the answer is 539/54
- In mixed form: 953/54
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