Subtract 45/90 from 20/50
20/50 - 45/90 is -1/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 90 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 50 × 9 = 450,
20/50 = 20 × 9/50 × 9 = 180/450 - Likewise, for the 2nd fraction, since 90 × 5 = 450,
45/90 = 45 × 5/90 × 5 = 225/450 - Subtract the two like fractions:
180/450 - 225/450 = 180 - 225/450 = -45/450 - After reducing the fraction, the answer is -1/10
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