Subtract 20/50 from 20/90
20/90 - 20/50 is -8/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 50 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 90 × 5 = 450,
20/90 = 20 × 5/90 × 5 = 100/450 - Likewise, for the 2nd fraction, since 50 × 9 = 450,
20/50 = 20 × 9/50 × 9 = 180/450 - Subtract the two like fractions:
100/450 - 180/450 = 100 - 180/450 = -80/450 - After reducing the fraction, the answer is -8/45
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