Subtract 81/18 from 6/20
1st number: 6/20, 2nd number: 4 9/18
6/20 - 81/18 is -21/5.
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,
6/20 = 6 × 9/20 × 9 = 54/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
81/18 = 81 × 10/18 × 10 = 810/180 - Subtract the two like fractions:
54/180 - 810/180 = 54 - 810/180 = -756/180 - After reducing the fraction, the answer is -21/5
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