Statistics Quiz

In a sample of 800 students in a university, 160, or 20%, are Business majors. Based on the above information, the school's paper reported that '20% of all the students at the university are Business majors.' This report is an example of

A statistics professor asked students in a class their ages. On the basis of this information, the professor states that the average age of all the students in the university is 21 years. This is an example of

If a normally distributed group of test scores have a mean of 70 and a standard deviation of 12, find the percentage of scores that will fall below 50.

When the majority of the data values fall to the right of the mean, the distribution is said to be left-skewed.

The normal distribution curve can be used as probability distribution curve for normally distributed variables.

X is normally distributed random variable with a mean of 10 and a standard deviation of 4.0. Find the value of X for which 70.54% of the are under the normal curve lies to the right of it.

Find the area under the standard normal distribution curve between z=-2.05 and z=2.05.

The mean of a sample is

• always equal to the mean of the population

• always smaller than the mean of the population

• computed by summing the data values and dividing the sum by (n - 1)

• computed by summing all the data values and dividing the sum by the number of items

• None of the above answers is correct.

Which of the following is not a measure of dispersion?

• the range

• the 50th percentile

• the standard deviation

• the interquartile range

• the variance

is an example of a

• population parameter

• sample statistic

• population variance

• mode

• none of the above answers is correct