Reference no: EM132606807
QUESTION ONE
State the properties of valiance.
QUESTION TWO
Suppose there are eight machines to be displayed in a shop but only four spaces are available. In how many will the machine be ordered?
QUESTION THREE
A committee of four must be selected from three women and four men. Calculate;
How many ways can the committee be formed.
In how many ways the committee be formed by two men and two women.
Find the probability of (b) above.
In how many ways the committee consists of at least two women.
Find the probability that the committee consists of at least two women.
QUESTION FOUR
A bulb company makes bulbs whose half-life is normally distributed with mean of 100 hours and standard deviation of 20 hours. What proportion of the bulb produced by this company will have a lifetime between 110-140 hours?
QUESTION FIVE
The time taken by workers to complete a certain job is normally distributed with mean of 160 minutes an standard deviation of 30 minutes.
What is the probability that a randomly selected worker takes more than 210 minutes to complete the task?
Calculate the probability that a randomly selected worker takes more 90 minutes.
QUESTION SIX
The results of random sample of children with pain from musculoskeletal injuries treated with acetaminophen, ibuprofen, or codeine are shown in the table. At α=0.10, is there enough evidence to conclude that the treatment and result are independent?
Acetaminophen (c.1) Ibuprofen (c.2) Codeine (c.3) Total
(r.1) significant improvement 58 81 61 200
(r.2) slight improvement 42 19 39 100
Total 100 100 100 300
QUESTION SEVEN
A study of the heights of 18 pairs of fathers and their sons shows the co-efficient of correlation is 0.52. Apply the t-test to find whether the correlation is significant at 5% level of significance.