Subtract 28/90 from 1/20
1/20 - 28/90 is -47/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
1/20 = 1 × 9/20 × 9 = 9/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
28/90 = 28 × 2/90 × 2 = 56/180 - Subtract the two like fractions:
9/180 - 56/180 = 9 - 56/180 = -47/180
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