Bunuel wrote:
In a recent survey, Q people were asked whether they eat after 22:00 O'clock. 25 percent of the people answered positively and 40 percent of the rest were asked, at what time do they get up in the morning. Which of the following expressions represents the number of people who do not eat after 22:00 and were not asked about the time they get up in the morning?
A. 3Q/20.
B. Q/10.
C. 5Q/9.
D. 3Q/10.
E. 9Q/20.
The number of people who do not eat after 22:00 is 0.75Q. Therefore, 0.4(0.75Q) = 0.3Q
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