Statistics and Probability Answers

Suppose that the sitting​ back-to-knee length for a group of adults has a normal distribution with a mean of 24.5in. and a standard deviation of 1.1in. These data are often used in the design of different​ seats, including aircraft​ seats, train​ seats, theater​ seats, and classroom seats. Instead of using 0.05 for identifying significant​ values, use the criteria that a value x is significantly high if​ P(x or ​greater)0.01 and a value is significantly low if​ P(x or ​less)0.01. Find the​ back-to-knee lengths separating significant values from those that are not significant. Using these​ criteria, is a​ back-to-knee length of 26.7in. significantly​ high?

The weight (x grams) of a rose is assumed to be distrubuted as N (5, 12.4). A rose is selected randomly .find the probability that the weight of randomly selected flower is less than 4 gram

Given the population 3 5 8 9 and 10. Suppose samples of size 3 are drawn from this population

a consider the normal distribution of IQs with a mean of 100 and a standard deviation of 16. What

percentage of IQs are?

a. greater than 95?

b. less than 120

c. between 90 and 110

A division-wide aptitude test in Science was conducted to 1000 pupils. The mean of the test is 58 and the standard deviation is 12. The scores also approximate the normal distribution. What is the score that divides the distribution into two such that 75% of the cases is below it?

Faculty salaries for a random sample of teacher in the public school system certain town recorded by dividing each salary 1,000 find the m a d and standard deviation of these salaries if the coded observation are 18,15,21,19,13,15,14,23,18 1nd 16pesos

Suppose the mean number of days to germination of a variety of seeds is 34, with a standard deviation of 4.3 days. What is the probability that the mean germination time of a sample of 250 seeds will be within 0.5 days of the population mean?

An electronic company in Laguna manufactures resistors that have a mean resistance of 120 ohms and a standard deviation of 13 ohms. Find the probability that a random sample of 40 resistors will have an average resistance greater than 114 ohms. 

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?

How many ways can 4 baseball players and 3 basketball players be selected from 12 baseball players and 9 basketball players?