2.) Scores on a national exam are normally distributed with a mean 500 and a standard...

2.) Scores on a national exam are normally distributed with a mean 500 and a standard deviation of 20. Find the score corresponding to the 70th percentile. use the table or excel.

3.) X is a binomial random variable with parameters n=5 and p= .5. Use the table to compute the probability indicated. P(x= 3). Round to four decimal places.

4.) A uniform distribution has a density curve that spans over the interval [3,7]. what height will the curve have to be on the y-axis?

5.) The probability that a part is defective is .05. A box contains 10 such prts. Find the probability that at least one of the parts is defective. use the tables.

6.) Two hundred raffle tickets are sold at $1 each. One ticket will win $1000 and 2 tickets will win $500. Let x denote the net gain from the purchase of a randomly selected ticket. compute the expected value E(x).

Expert Solution

Ans (2) Let random variable X denote national axam score

orchestra answered 1 year ago

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