Statistics and Probability Answers

There are 7 boys and 5 girls in a youngsters’ club. A committee of 3 boys and 2 girls is to be chosen. How many different possibilities are there?

The average weight of ten bulls is 500kg and the standard deviation of the weight is 30kg. What would be the weight of a bull that is 6 standard deviation above the mean weight?

A committee of 4 men and 6 women is to be selected from 7 men and 8 women. If there is a married couple among the 15 people, in how many ways can the committee be selected so that the couple are automatically in the committee?

The following attributes are measured for members of a herd of Asian elephants:

weight, height, tusk length, trunk length, and ear area. Based on these

measurements, what sort of similarity measure from Section 2.4 would you use

to compare or group these elephants? Justify your answer and explain any

special circumstances.

A lot consists of 10 good articles, 4 with minor defects and 2 with major defects.

i. One article is chosen at random. Find the probability that

a. It has no defects, c) It is either good or has major defects.

b. It has no major defects,

Tubeit-Biner et al. (A-9) found that the number of serious gastrointestinal reactions reported to British Committee on Safety of Medicine was 538 for 9,160,000 prescriptions of the anti-inflamma drag piroticam. This corresponds to a rate of 058 gastrointestinal reactions per 1000 prescriptio written. Using a Poisson model for probability, with A-06, find the probability of (a) Exactly one gastrointestinal reaction in 1000 prescriptions (b) Exactly two gastrointestinal reactions in 1000 prescriptions (c) No gastrointestinal reactions in 1000 prescriptions (d) At least one gastrointestinal reaction in 1000 prescriptions

find the variance and standard deviation of the probability distribution of the random variable W if P{W = w} = {w+1}/20 for W = {1, 2, 3, 4, 5}

Read and analyze the following situations and supply the values of the following variables (if

there is any). On the third column, write known on the space provided if the situation gives

or can compute the value of the variance, otherwise write unknown. Identify also the formula

to be used to estimate the standard error of the mean by writing the symbols or, when the

population variance is known and sxwhen the population variance is unknown,

Situation:

A population composed of 11 items whose

N=

measurements are 12, 7, 9,11,8, 20, 23, 18, 13, 22.

and 10. Samples of 5 items are drawn at random

without replacement.

Given: N=

n=

Answer:

Standard Error Formula:

The random variable X is best described by a normal distribution with mean of 30 and standard deviation of 6. Find the z-score that corresponds to th following X values. a. X = 21 b. X = 26 c. X = 35 d. X = 42 e. X = 50