Subtract 70/18 from 42/81
1st number: 42/81, 2nd number: 3 16/18
42/81 - 70/18 is -91/27.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 18 is 162
Next, find the equivalent fraction of both fractional numbers with denominator 162 - For the 1st fraction, since 81 × 2 = 162,
42/81 = 42 × 2/81 × 2 = 84/162 - Likewise, for the 2nd fraction, since 18 × 9 = 162,
70/18 = 70 × 9/18 × 9 = 630/162 - Subtract the two like fractions:
84/162 - 630/162 = 84 - 630/162 = -546/162 - After reducing the fraction, the answer is -91/27
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