Subtract 27/28 from 18/20
18/20 - 27/28 is -9/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 28 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
18/20 = 18 × 7/20 × 7 = 126/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
27/28 = 27 × 5/28 × 5 = 135/140 - Subtract the two like fractions:
126/140 - 135/140 = 126 - 135/140 = -9/140
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