Theo sốliệu thống kê ởmột khu vui chơi cho trẻem, sốlượng trẻbịlạc bốmẹtrong ngày thứ7 là biến ngẫu nhiên X có bảng phân phối xác suất như sau:X01234P0.30.30.20.10.1a) Tìm kỳvọng ()EXvà phương sai (2).DXb) Giảsửkhi trẻbịlạc sẽcó 3 thông báo liên tiếp được phát ra từhệthống do bốmẹyêu cầu. Gọi Y là sốthông báo phát ra vềtrẻbịlạc trong ngày thứ7. Tính xác suất (8).

Logan wants to know how many skateboards have defective parts. he inspects 20,000 skateboards and keeps track of the number of defects per board. use his probability distribution table to find the expected value for defects on a skateboard.

Suppose that 3% of all athletes are using the endurance-enhancing hormone epo (you should be able to simply compute the percentage of all athletes that are not using epo). for our purposes, a “positive” test result is one that indicates presence of epo in an athlete’s bloodstream. the probability of a positive result, given the presence of epo is .99. the probability of a negative result, when epo is not present, is .90. what is the probability that a randomly selected athlete tests positive for epo? 0.0297

Simplify (2^5/3^2)^4 a. 2^20/3^8 b. 2^9/3^8 c. 8^5/12^2 d. 2/3^2