Reference no: EM132116652

1. A research study examined the blood vitamin D levels of the entire US population of landscape gardeners. The population average level of vitamin D in US landscapers was found to be 45.72 ng/mL with a standard deviation of 5.922 ng/mL. Assuming the true distribution of blood vitamin D levels follows a normal distribution, if you randomly select a landscaper in the US, what is the probability that his/her vitamin D level will be 49.61 ng/mL or more?

2. A research study examined the blood vitamin D levels of the entire US population of landscape gardeners. The population average level of vitamin D in US landscapers was found to be 47.47 ng/mL with a standard deviation of 5.986 ng/mL. Assuming the true distribution of blood vitamin D levels follows a normal distribution, what is the 31-st percentile? Recall that the statistic, "percentile", is defined to be the value below which a given percentage of observations are located within the distribution. In other words, for this question find the vitamin D value for which 31% of the observations within the distribution are located to the left of this value.