## CSETMathGuru: THE Site for Single Subject Math

**Are you prepared for the Statistics portion of Subtest II: Geometry/Statistics?**

Then, have a stab at the following!

Assess yourself: You should do OK on the Test if you could solve 4 of the 5 Qs below, taking about 20 minutes/Q!

5. The fat and corresponding calorie content for 5oz of 7 kinds of pizza are given below:

Fat (in grams): ---- 9-----16----14-----9----10----11----13

Calories:--------- 306---383---339---328---310---314---350

a) Plot the points using an appropriate scale.

b) Calculate the Least Squares Regression Line (LSRL) by hand.

c) Interpret the slope and y-intercept of the LSRL.

d) Verify that the LSRL goes through the point of averages (x-bar, y-bar).

4. The costs per load (in cents) of 35 detergents tested by Consumer Reports are shown below:

Costs *********** Frequency

13-19.9 ************* 2

20-26.9 ************* 7

27-33.9 ************* 12

34-40.9 ************* 5

41-47.9 ************* 6

48-54.9 ************* 1

55-61.9 ************* 0

62-68.9 ************* 2

a) Draw a frequency and cumulative frequency distribution for the data.

b) Calculate the mean, median and modal costs per load of the 35 detergents. Interpret each.

c) Compute the standard deviation and variance. Interpret each.

3. The heights of male 18-24 year olds in the US is roughly normally distributed with a mean of 70.1in and a standard deviation of 2.7in.

a) If a US male in the 18-24 age group were selected at random, calculate the probability that he is less than 66in tall?

b) Out of the roughly 13mn US males between 18-24 years, roughly how many have heights between 68in and 71in?

c) Calculate the height that constitutes the 70th percentile for this population.

2. The distribution of colors for plain M&Ms is given below:

Red (20%), Yellow (20%), Green (10%), Orange(10%), Brown (30%) and Blue (10%). If a random sample of 75 peanut M&Ms yields the following distribution of colors: Red (14), Yellow (15), Green (6), Orange(8), Brown (23) and Blue (9), is the distribution of colors of peanut M&Ms the same as that of plain M&Ms?

To answer the question,

a) State an appropriate hypothesis.

b) Perform a Chi-Square test to test the hypothesis at the 5% significance level.

c) Interpret the P-value in the context of the question.

1. A quality control inspector examines DVD players for a complete inspection as they come off an assembly line. It is known that 10% of all items are defective. Also, 60% of all defective items and 20% of all good items undergo a complete inspection.

a) If a randomly selected DVD player undergoes a complete inspection, what is the probability that it is defective?

b) If a certain DVD player did not undergo a complete inspection, what is the probability that it is not defective?