A normal distribution has μ = 80 and σ = 10.  What is the probability of randomly selecting a score greater than 90 from this distribution?​   a. ​0.6915   b. 0.8413​   c. ​0.3085   d. ​0.1587

A population of values has a normal distribution with M=153.9 and O=82.9 You intend to draw a random sample of size n=115. A). Find P86, which is the score separating the bottom 86% scores from the top 14% scores. P86 (for single values) =__________ B). Find P86, which is the mean separating the bottom 86% means from the top 14% means. P86 (for sample means) =_________

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Private nonprofit four-year colleges charge, on average, $26,796 per year in tuition and fees. The standard deviation is $6,782. Assume the distribution is normal. Let X be the cost for a randomly selected college. Round all answers to 4 decimal places where possible. a. What is the distribution of X? X N( 26796 6782 b. Find the probability that a randomly selected Private nonprofit four-year college will cost less than 31,080 per year. Enter an integer or decimal number, accurate to at least 4 decimnal places [more..] c. Find the 75th percentile for this distribution. $ (Round to the nearest dollar.)