Subtract 30/50 from 20/40
20/40 - 30/50 is -1/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 50 is 200
Next, find the equivalent fraction of both fractional numbers with denominator 200 - For the 1st fraction, since 40 × 5 = 200,
20/40 = 20 × 5/40 × 5 = 100/200 - Likewise, for the 2nd fraction, since 50 × 4 = 200,
30/50 = 30 × 4/50 × 4 = 120/200 - Subtract the two like fractions:
100/200 - 120/200 = 100 - 120/200 = -20/200 - After reducing the fraction, the answer is -1/10
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