x P(x) 0 0.05 1 0.15 2 0.15 3 0.65 Find the standard deviation of this probability distribution. Give your answer to at least 2 decimal places

The time that it takes for the next train to come follows a Uniform distribution with f(x) =1/45 where x goes between 4 and 49 minutes. Round answers to 4 decimal places when possible. Find the probability that the time will be at most 31 minutes.  Find the probability that the time will be between 9 and 48 minutes

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Find the standard deviation of this probability distribution. Give your answer to at least 2 decimal places

X P(x) 0 0.1 1 0.25 2 0.3 3 0.35 Find the standard deviation of this probability distribution. Give your answer to at least 2 decimal places

X P(X) 0.1 0.1 2 0.25 3 0.55 Find the standard deviation of this probability distribution. Give your answer to at least 2 decimal places

x P(x) 0 0.2 1 0.05 2 0.2 3 0.55 Find the standard deviation of this probability distribution. Give your answer to at least 2 decimal places

I am in Prob/Stat!   Find the standard deviation of this probability distribution. Give your answer to at least 2 decimal places. x P(x)     0 0.15 1 0.15 2 0.2 3 0.5 I have multiplied P by x, thus, P(x) as such: 0.15(0)   =   0 0.15(1)   =   0.15 0.2(2)      =   0.4 0.5(3)      =   1.5 I then add the four together to get the sum of; 2.05.   What am I doing wrong?  Am I not finding the standard deviation correctly?? Thank you in advance!

xx P(x)P(x) 0 0.15 1 0.05 2 0.2 3 0.6 Find the standard deviation of this probability distribution. Give your answer to at least 2 decimal places

IQ is normally distributed with a mean of 100 and a standard deviation of 15. Suppose one individual is randomly chosen. Let X = IQ of an individual. + Part (a) O Part (b) Part (c) Mensa is an organization whose members have the top 2% of all IQs. Find the minimum IQ needed to qualify for the Mensa organization. Write the probability statement. P(X > x) = |0.98