Normal Distribution

The area under the curve to the left of the unknown quantity must be 0.7 (70%). So, we must first find the z value that cuts off an area of 0.7 in the left tail of standard normal distribution. Using the cumulative probability table, we see that z=0.53.

5) Describe how the normal range for any given measurement is obtained. Explain why published values for normal ranges may differ and why these values must be continually checked and updated.

1. Are any of the lab values in Table 1 out of normal range? Do you see some that are too high or too

An intelligence test for which the scores are normally distributed has a mean of 100 and a standard deviation of 15. Use this information to describe how the scores are distributed.

a) Graph the following data on regular OR semi-log graph paper (graph both thermal death time curves on the same sheet of paper). Use the graph to determine the z-value for each organism. Show your work.

2. For the following set of scores, fill in the cells. The mean is 74.13 and the standard deviation is 9.98.

Step 4: The sample’s score on the comparison distribution is determined which in his case is Z=

| Z score (standardised value)-how many sds from the mean the value liesZ score = data value – mean Standard deviation

In order for you to understand how I did this, I will explain that a z-score gives you a way to compare different sets of data using their standard deviations and averages. In statistics, standard deviation is a measure that is used to quantify the amount of variation or dispersion of a set of data values. A standard deviation close to zero tells you the data points are close to the mean or average. Having a high standard deviation shows data points are spread out over a wider range of values. If x is a data point in a normal distribution, then the equation for the z-score of x is x equals x minus the average all divided by the standard deviation. Normal distribution is just a function that represents the distribution of many random variables as a symmetrical bell-shaped graph.

What is the probability that [pic] will be within 0.5 of the population mean? (5 points)

1. Assuming that the distribution is normal for weight relative to the ideal and 99% of the male participants scored between (–53.68, 64.64), where did 95% of the values for weight relative to the ideal lie? Round your answer to two decimal places.

To perform a certain type of blood analysis, lab technicians must perform two procedures. The first procedure requires either one or two separate steps, and the second procedure requires either one, two, or three steps.

At 50, the z-value is -60/29.39=-2.04 The probability that z is less than this number is .0207. Since the probability of being less than 120 was implied in part d of being .6331, the probability of landing between the two is the difference: .6124.

T = 47 days, TE = 43.17 days, and the sum of the variances for the critical activities is: (0.25 + 5.44 + 0.69 + 2.25) = 8.63. z T  TE  47  43.17 8.63  3.83  1.30 2.94

Calculate this value for each alternative, and fill in the blank on the row for σ in the table above.