Math Answers

How long does it take for 900 to accumulate to 1000 under an interest rate of 4% per annum?

A vendor claims that the variance for measurement of tiles that his factory produce were 13 square feet. A sample of nine tiles was measured in square feet and the results of the tiles produced were recorded as below:

204.5 206.3 202.4 207.8 203.1 206.2 203.8 206.6 205.8

(Assuming the sample comes from a normal population)

i) Calculate the point estimate of the population mean. (2 marks)

ii) Compute the variance and standard deviation. (3 marks)

iii) Determine the estimate of 95% confidence interval for the population mean of the tiles. (5 marks)

Prove that an ideal M neq R in a commutative ring R with identity is maximal if and only if for every r in R-M, there exists x in R such that 1_R - rx in M.

a population consistent of two numbers (3,7) consider all possible samples of size n=3 which can be drawn with replacement from the population

a person may earn 100,000.00 by investing in the stocks of an international company with a probability of 0.40 or lose 35,000,00 over the same period with a probability of 0.60. Let X denote the net gain of a perspn who will invest in the company construct the probability distribution of X, and the compute for the expected value of a person who will invest in the same company. ​

The following data give the numbers of orders received for a sample of 30 items at the Time-saver Mail Order Company.

34 44 31 52 41 47 38 35 32 39

28 24 46 41 49 53 57 33 27 37

30 27 45 38 34 46 36 30 47 50

Using 6 classes of equal width, construct a grouped frequency distribution of the above data. Let 22 be the

lower limit of the initial class.

Question 2 (5 Marks)

Calculate the median.

Question 3 (6 Marks)

Calculate the mid-70% range.

Question 4 (11 Marks)

Calculate the coefficient of variation and interpret the value obtained.

n= 15 Percentile= 99.5th t(a,df)=

Determine whether if lim f(c) = f(c)

x→c

1. f(x) = x+2; c = -1

2. f(x) = x-2; c = 0

3. (at c = -1 )

f(x) = {x ² - 1 if x < -1}

f(x) = { (x - 1) ² - 4 if x ≥ -1}

4. (at c = 1 )

f(x) = {x³ - 1 if x < 1}

f(x) = { x² + 4 if x ≥ 1}

The average time it takes for a high school students to complete certain examination is 46.2 minutes. The standard deviation is 8 minutes. There will be 50 random samples to be selected. Assume that the variable is normally distributed.

1. What is the population mean in the given problem?

a. 0

b. 8

c. 46.2

d. 50

2. What is the value of n in the given problem?

a. 0

b. 8

c. 46.2

d. 50

3. If 50 random selected high school students take the exam, what is the probability that the mean time it takes the group to complete the test will be less than 43 minutes?

a. 0.23%

b. 2.3%

c. 3%

d. 23%

What is the standard deviation of sampling distribution if standard deviation of population is 35 and sample size is 9?