Statistics and Probability Answers

The mean weekly a sales of soap bars in different departmental stores was 146.3 bars per store. after an advertising campaign the mean weekly increased to 153.7 and showed a standard deviation of 72.2. Was the advertising campaign successful at 5% level of significance? You may like to use the values given at end.

A beer company wants to determine the mean weight of a can of its beer. It takes a random sample of 80 such cans (from several thousand cans in its warehouse) and finds that the mean weight is 31.15 ounces and the standard deviation is 0.08 ounce.
1. Compute a 95% confidence interval for the mean weight of the cans in the firm warehouse.
2. Is your answer to 1. based on the assumptions that the weights of the cans of beer in the warehouse are normally distributed? Why or why not?

there are 5 men and 5 women to be selected to make a committee of 5 members what is the probability that all committee members are from one gender?

A chartered Accountant applies for a job in two firms X and Y. He estimates that the profitability of his being selected in firm X is 0.7. and being rejected in Y is 0.5 and the probability that at least one of his applications rejected is 0.6. What is the probability that he will be selected in one of the firms.

can a ratio variable be reduced to a ordinal variable? can an ordinal variable be promoted to a ratio variable? can an ordinal variable be reduced to a nominal variable?

P(A|B)=.71 , P(A|B')=.81 , P(B)=.25 what is P(B|A)

A new analytical method to detect pollutants in water is being tested. instead of having to use a single test for each pollutant. The makers of the test claim that it can detect high levels of organic pollutants with 99.6% accuracy, volatile solvents with 99.94% accuracy, and chlorinated compounds with 89.8% accuracy. If a pollutant is not present, the test does not signal. Samples are prepared for the calibration of the test and 60% of them are contaminated with organic pollutants, 27% with volatile solvents, and 13% with traces of chlorinated compounds. A test sample is selected randomly.

(a) What is the probability that the test will signal?

The data which has been collected for some other enquiry order than the one of immediate interest is called ……..

Secondary data
Literature
Observation
Primary data

A ………………….is a selection of n distinct objects without regard to order

permutation
distribution
pascal
combination

An ............ is a repetitive activity carried out for an expected result.

sample space
sample
experiment
statistics