Four 6-sided dice are rolled. The dice are fair, so each one has equal probability of producing a value in 1, 2, 3, 4, 5, 6 . Let X = the minimum of the four values rolled. (It is fine if more than one of the dice has the minimal value.). What is P (X ≥ k) as a function of k?

You were told that the amount of time lapsed between consecutive trades on the new york stock exchange followed a normal distribution with a mean of 15 seconds. you were also told that the probability that the time lapsed between two consecutive trades to fall between 16 to 17 seconds was 13%. the probability that the time lapsed between two consecutive trades would fall below 13 seconds was 7%. what is the probability that the time lapsed between two consecutive trades will be between 14 and 15 seconds?