Cho thí nghiệm ngẫu nhiên có không gian mẫu và bảng phân phối xác suất X 0 1 2 3 4 5
P 0,1 0,2 0,1 0,4 0,1 0,1
Hãy tính xác suất:
a. A = {0,3,5}.
b. B = “Số lẻ”.
c. C = “Số lớn hơn 2”.
d. D = “Số lớn hơn 6”.
e. Tìm ModX, EX, V arX.
f. Tính P(−1 < X < 3); P(|X − EX| < 2,5); P(|X − EX| > 3,1).

At the olympic games, many events have several rounds of competition. one of these events is the men's 100-meter backstroke. the upper dot plot shows the times (in seconds) of the top 8 finishers in the final round of the 2012 olympics. the lower dot plot shows the times of the same 8 swimmers, but in the semifinal round. which pieces of information can be gathered from these dot plots? (remember that lower swim times are faster.) choose all answers that apply: a: the swimmers had faster times on average in the final round. b: the times in the final round vary noticeably more than the times in the semifinal round. c: none of the above.