Search & Filtering
Use the steps to solve the following problems
1. A politician engaged the services of a private opinion pollster to determine the sample size needed among his constituents to interview about their perceptions on the freedom of information bill. Previous polls revealed that
approximately 62.5% are in favor of the bill. The politician adopted the 0.95 level of confidence and off the population value by at most 0.02.
2. A transportation company wants to know the amount of time it takes a bus
to travel from one bus stop to the next. From past observations, the standard
deviation is 5 hours. How many measurements are needed in order to be 95% certain that
the maximum error of estimate will not exceed 1 hour? What sample size is required for a maximum error of 2 hours?
Determine whether the test is two-tailed or one-tailed. If it is one-tailed, is it left-tailed or right-tailed? Sketch the graphical representation of the test.
1. A nutritionist claims that her developed bread is fortified with vitamin B.
2. A musician believes that listening to classical music affects mood.
3. A storekeeper thinks that time of day influences sale of ice cream.
4. A mother wants to prove that reading books to children improves their thinking processes.
5. A certain combination of fruits provides the daily requirement for vitamin C.
A student has to take 12 more courses before he can graduate. If none of the courses are prerequisite to others, how many groups of four courses can he select for the next semester?
Find the Probabilities on a standard normal curve
1. P(z>—1.32)
2. P(z< 0.45)
3. P(—2.76 < z < 2.76)
4. P(—3.0 < z < —1.68)
5. P(1.53 < z <2.91)
Regarding the general multiplication rule and the conditional probability rule:
b. Explain the relationship between them.
c. Why are two different variations of essentially the same rule emphasized?
Test marks (%) obtained in a test are normally distributed with a mean of 55% and variance of 400(% squared). What is the probability that a randomly selected student scored above 60%?
A short term insurance company receives three vehicle claims related calls, on average, per hour. Assume that the daily claims follow a poisson process. how many claims related calls does company expect to receive in a period of three hours?
The diameter of an electric cable, Say X, is assumed to be continuous random variable with p.d.f f(x)=6x(1-x), 0<x<1.
A. Show that f(x) is a p.d.f.
B. Determine a number b such that P(X<b)= P(X >b).
C. Find the mean of x.
If on the average, (5 + 1) cars enter a certain parking lot per minute, what is the probability that during any given minute (i): 4 or more cars will enter the lot? (ii): exactly 4 cars will enter?
The Gauteng chamber of business conducted a survey amongst 17 furniture retailers to identify the percentage of bad debts in each company’s debtors’ book. The bad debts percentages are as follows:
2.2, 4.7, 6.3, 5.8, 5.7, 7.2, 2.6, 2.4, 6.1, 6.8, 2.2, 5.7, 3.4, 6.6, 1.8, 4.4, 5.4
Calculate the Pearson Coefficient of skewness coefficient for percentage of bad debts. Is the data skewed?
#340153 on Dec 2023