Subtract 81/18 from 40/20
1st number: 2 0/20, 2nd number: 4 9/18
40/20 - 81/18 is -5/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 18 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
40/20 = 40 × 9/20 × 9 = 360/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
81/18 = 81 × 10/18 × 10 = 810/180 - Subtract the two like fractions:
360/180 - 810/180 = 360 - 810/180 = -450/180 - After reducing the fraction, the answer is -5/2
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