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سؤال 116

A bag holds 8 counters, 3 of them red. A counter is drawn at random and returned to the bag, and this is repeated 80 times. About how many red counters would you expect to draw? Enter the number of red draws.

پاسخ درست

30 · واحدهای پذیرفته‌شده: draws · red draws · counters · times

توضیح

Because the counter goes back each time, every draw gives red with the same probability of 3 out of 8, and three eighths of 80 draws is 30. Multiplying 3 by 8 gives 24, a figure built only from the description of the bag, which leaves out the 80 draws the question is actually about.

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شروع تمرین
سؤال 116: A bag holds 8 counters, 3 of them red. A counter is drawn… · Statistics and Probability · Questena