A used-cars salesman receives an annual bonus if he meets a certain
quota. This year, the salesman has so far sold $$\frac{1}{5}$$ of last year's
quota. If this year's quota is reduced by 25 percent from last year, the quantity that he still needs to sell this year in order to receive the annual bonus is what fraction of
the preceding year's car quota?

Correct.
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So far this year, the salesman has sold $$\frac{1}{5}\times 20 = 4$$ cars. Now, he gets the good news that this year's quota is reduced by $$25\% = \frac{1}{4}$$.
>$$\frac{1}{4}\times 20 = 5$$ cars,
so he only needs to sell a total of $$20-5=15$$ cars this year to qualify for the bonus. Thus, he still needs $$15-4=11$$ cars.
The 11 cars out of the preceding year's car quota of 20 is $$\frac{11}{20}$$. Thus, D is the right answer.

Incorrect.
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Incorrect.
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Incorrect.
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Incorrect.
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$$\frac{1}{5}$$

$$\frac{4}{15}$$

$$\frac{9}{20}$$

$$\frac{11}{20}$$

$$\frac{3}{4}$$