Subtract 21/40 from 20/50
20/50 - 21/40 is -1/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 40 is 200
Next, find the equivalent fraction of both fractional numbers with denominator 200 - For the 1st fraction, since 50 × 4 = 200,
20/50 = 20 × 4/50 × 4 = 80/200 - Likewise, for the 2nd fraction, since 40 × 5 = 200,
21/40 = 21 × 5/40 × 5 = 105/200 - Subtract the two like fractions:
80/200 - 105/200 = 80 - 105/200 = -25/200 - After reducing the fraction, the answer is -1/8
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