Subtract 18/81 from 42/2
1st number: 21 0/2, 2nd number: 18/81
42/2 - 18/81 is 187/9.
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,
42/2 = 42 × 81/2 × 81 = 3402/162 - Likewise, for the 2nd fraction, since 81 × 2 = 162,
18/81 = 18 × 2/81 × 2 = 36/162 - Subtract the two like fractions:
3402/162 - 36/162 = 3402 - 36/162 = 3366/162 - After reducing the fraction, the answer is 187/9
- In mixed form: 207/9
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