Subtract 8/18 from 7/20
7/20 - 8/18 is -17/180.
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,
7/20 = 7 × 9/20 × 9 = 63/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
8/18 = 8 × 10/18 × 10 = 80/180 - Subtract the two like fractions:
63/180 - 80/180 = 63 - 80/180 = -17/180
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