Subtract 40/50 from 21/40
21/40 - 40/50 is -11/40.
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,
21/40 = 21 × 5/40 × 5 = 105/200 - Likewise, for the 2nd fraction, since 50 × 4 = 200,
40/50 = 40 × 4/50 × 4 = 160/200 - Subtract the two like fractions:
105/200 - 160/200 = 105 - 160/200 = -55/200 - After reducing the fraction, the answer is -11/40
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