Subtract 20/36 from 45/90
45/90 - 20/36 is -1/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 36 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
45/90 = 45 × 2/90 × 2 = 90/180 - Likewise, for the 2nd fraction, since 36 × 5 = 180,
20/36 = 20 × 5/36 × 5 = 100/180 - Subtract the two like fractions:
90/180 - 100/180 = 90 - 100/180 = -10/180 - After reducing the fraction, the answer is -1/18
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