Subtract 40/81 from 7/18
7/18 - 40/81 is -17/162.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 81 is 162
Next, find the equivalent fraction of both fractional numbers with denominator 162 - For the 1st fraction, since 18 × 9 = 162,
7/18 = 7 × 9/18 × 9 = 63/162 - Likewise, for the 2nd fraction, since 81 × 2 = 162,
40/81 = 40 × 2/81 × 2 = 80/162 - Subtract the two like fractions:
63/162 - 80/162 = 63 - 80/162 = -17/162
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