Subtract 20/45 from 28/90
28/90 - 20/45 is -2/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
28/90 = 28 × 1/90 × 1 = 28/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
20/45 = 20 × 2/45 × 2 = 40/90 - Subtract the two like fractions:
28/90 - 40/90 = 28 - 40/90 = -12/90 - After reducing the fraction, the answer is -2/15
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