variable distributions

Random Variables and Probability Distributions - It is often very important to allocate a numerical value to an outcome of a random experiment. For example, consider an experiment of tossing a coin twice and note the number of heads (x) obtained. Outcome HH HT TH TT No. of heads..

Let S be a sample space associated with a given random experiment. A real valued function X which assigns to each w i S, a unique real number, X( w i ) = x i is called a random variable . Two types of random variables are 1. Continuous random variableh..

It is often very important to allocate a numerical value to an outcome of a random experiment. For example, consider an experiment of tossing a coin twice and note the number of heads (x) obtained. Outcome HH HT TH TT No. of heads (x) 2 1 1 0 x is called a random variable, which can assum..

A chi-square variable cannot be _____, and the distributions are _____ skewed. => positive ; negatively or 0 ; positively or 1 ; negatively or negative ; positively..

What formula is used to gain information about a sample mean when the variable is normally distributed or when the sample size is 30 or more? => z = X - μ σ or z = X ‾ - μ σ n or z = X ‾ - μ σ n or z = X - μ σ..

Find the 95% confidence interval for the variance of the ages of players in a basketball team if a sample of 12 players has a standard deviation of 2 years. Assume the variable is normally distributed. => between 2 and 10 or between 2 and 13 or between 2 and 14 or between 2 and ..

A sample of 30 RAM chips was tested for the average access time. The standard deviation was found to be 2 nanosec. Find the 90% confidence interval for the true standard deviation. Assume that the variable is normally distributed. => between 1.7 and 2.6 or between 1.6 and 2.5 or..

The daily water usage (in gallons per person per day) of 10 families of a colony has a variance of 286. Find the 90% confidence interval for the variance and standard deviation. Assume that the variable is normally distributed. => 152 < σ 2 < 774 ; 12 < σ &l..

The average age of media reporters worldwide is 35 years with a standard deviation of 6 years. If a media channel employs 50 media reporters, then what is the probability that their mean age lies between 34 and 37 years? Assume that the variable is normally distributed. => 87.15..

The mean time a student spends on a computer is 4 hours per day. Assume the standard deviation is 0.7 hour. Find the percentage of students who spend more than 4.3 hours on the computer. Assume the variable is normally distributed. => 66.56% or 88.44% or 33.36% or 16.56%..