Statistics and Probability Answers

Roll a single number cube 20 times record the number of times it lands on three for any single roll what is the probability that the cube lands on three

Data collected from a website show that 60% of visitors you scavenger as their web browser you randomly select 100 visitors from the website and record how many you scavenger for any single visitor what is the probability that they do not use scavenger

Tossing 4 coins simultaneously finds the probability of getting 2 heads and 2 tails. 

There are 15 balls in an urn. 5 red balls, 5 blue balls, and 5 white balls. Three balls are taken simultaneously.

The 95% confidence interval for the variance and standard deviation for the sugar content in an ice cream (in mg) if the sample of nine servings has a variance of 36.

An ambulance service claims that it takes on the average 8.9 minutes to reach its destination in emergency calls. To check on this claim, the agency which licenses ambulance services has then timed on 50 emergency calls, getting a mean of 9.3 minutes with a standard deviation of 1.8 minutes. Does this constitute evidence that the figure claimed is two low at 1 per cent significance level?

1.   Dr. Cornie developed a test to measure Boredom. He administered it to a group of 20,000 adults. The possible scores were 1, 2, 3, 4, 5, 6, and 7 with 7 indicating the highest tolerance for boredom. The results are shown. Complete the following table and then find the mean, variance, and standard deviation to measure boredom tolerance of the adults.

Score X

1

2

3

4

5

6

7

Frequency f

1400

2600

3600

6000

4400

1600

400

Probability P(X)

1.   An investor is pondering on whether to invest in a siomai franchise or in a printing press company. He had his staff analyze the cost benefits that he would get from the two business ventures. Show the report of each business.

A.   The siomai franchise would need Php 800 000 as capital. It has a 60-percent chance of profiting Php 400 000; a 15-percent chance of profiting Php 600 000; and 25-percent chance of losing the capital entirely.

B.   The paper manufacturing company would need Php 800 000 as capital. It has a 35-percent chance of earning Php 1 000 000 and a 65-percent chance of losing the capital entirely.

C.  Which between the two business ventures should the investor invest his Php 800 000?

A fertilizer mixing machine is set to give 12 Kg of nitrate for every 100 kg of fertilizer. Ten bags of 100 kg each are examined. The percentage of nitrate so obtained is: 11,14,13,12,13, 12,13,14,11and 12. Is there reason to believe that the machine is defective, given that the population from where the sample has been drawn assumes normality? ( Test the hypothesis at 1% level of significance)

The data for the promotion status and academic qualification regarding 100 employees of a company is as follows:

Promotional. MBA. Academic qualification. Total

Status. Non - MBA

Promoted. 12. 48. 60

Not promoted. 18. 22. 40

Total. 30. 70. 100

At random one employee is picked up. What is the probability that:

1. He is MBA

2. He is promoted

3. He is promoted given that he is an MBA, and

4. He is an MBA given that he is promoted

5. He is promoted and MBA too?