100 mL of a solution of compound “X” has the following properties:

–Molarity: 2M –MW of “X”: 500g/mole

–Density of compound “X”: 5.0g/cm3

What dilution factor would be required to make a solution of 1% (v/v) of “X”?

Do female college students spend more time than male college students watching TV? This was one of the questions investigated by the authors of an article. Each student in a random sample of 46 male students at a university in England and each student in a random sample of 38 female students from the same university kept a diary of how he or she spent time over a three-week period. For the sample of males, the mean time spent watching TV per day was 68.7 minutes and the standard deviation was 67.5 minutes. For the sample of females, the mean time spent watching TV per day was 93.9 minutes and the standard deviation was 89.1 minutes. Is there convincing evidence that the mean time female students at this university spend watching TV is greater than the mean time for male students? Test the appropriate hypotheses using α = 0.05. (Use a statistical computer package to calculate the P-value. Use μmales − μfemales. Round your test statistic to two decimal places, your df down to the nearest whole number, and your P-value to three decimal places.)

t = 1.4739 Incorrect: Your answer is incorrect.

df = 82 Incorrect: Your answer is incorrect.

P-value = 0.288 Incorrect: Your answer is incorrect.

State your conclusion. Fail to reject H0. We do not have convincing evidence that the mean time female students at this university spend watching TV is greater than the mean time for male students. Fail to reject H0. We have convincing evidence that the mean time female students at this university spend watching TV is greater than the mean time for male students. Reject H0. We do not have convincing evidence that the mean time female students at this university spend watching TV is greater than the mean time for male students. Reject H0. We have convincing evidence that the mean time female students at this university spend watching TV is greater than the mean time for male students.

Please show your work so I can follow along!!!!! Thank you.

Med Student Sleep Average: Here we consider a small study on the sleep habits of med students and non-med students. The study consists of the hours of sleep per night obtained from 32 non-med students and 24 med students. The summarized data is given in the table below. Here,

x is the mean hours of sleep per night from each sample.

Necessary information:

The Test: Test the claim that, on average, the mean hours of sleep for all med students is different from that for non-med students. Test this claim at the 0.01 significance level.

(a) The claim states there is a difference between population means (μ₁ − μ₂ ≠ 0). What type of test is this?

This is a two-tailed test.

This is a right-tailed test.  

  This is a left-tailed test.

(b) Calculate the test statistic using software or the formula below

t =

where δ is the hypothesized difference in means from the null hypothesis. Round your answer to 2 decimal places.
t =
To account for hand calculations -vs- software, your answer must be within 0.01 of the true answer.

(c) Use software to get the P-value of the test statistic. Round to 4 decimal places.
P-value =

(d) What is the conclusion regarding the null hypothesis?

reject H₀

fail to reject H₀    

(e) Choose the appropriate concluding statement.

The data supports the claim that, on average, the mean hours of sleep for all med students is different from that for non-med students.

There is not enough data to support the claim that, on average, the mean hours of sleep for all med students is different from that for non-med students.

We reject the claim that, on average, the mean hours of sleep for all med students is different from that for non-med students.

We have proven that, on average, the mean hours of sleep for all med students is different from that for non-med students.

A transformer is a device that takes advantage of Faraday’s Law to change an AC voltage. It consists of a primary coil and a secondary coil. When a transformer is used to raise the voltage, it is called step-up transformer and when used to lower the voltage, it is called a step-down transformer. As in the case of nested coils discussed in the Pre-Lab Notes, the secondary coil has a varying magnetic field in its center due to the varying electric current (i.e., AC current) in the primary coil. The induced current and electric potential may be different in the secondary coil than in the primary coil. For N_P loops in the primary coil, N_S turns of the wire in the secondary, and a voltage supplied by the power source of V_P, the induced voltage in the secondary is given by

         (1) V S = N S N P V P

The induced current is

         (2) I S = N P N S I P

The second challenge is to find the ratio of the turns of the outer coil to the inner coil in the nested coil set. The constraint here is that you must use electromagnetic induction in your technique. Another minor limitation is that you don’t have access to the lab equipment. Two data sets are provided for you, You need to analyze them and come to conclusions.

The first data set is for a pair of nested coils, with the inner being the primary with an applied AC voltage at 60 Hz and the outer being the secondary. For the second data set, the primary and secondary roles are reversed.

Copy each of these data sets into Excel, graph them. And find the best fit. Upload the worksheet here.

CASE STUDY – INTERNAL CONTROL

Honkydory Musical School wants to raise money for a new sound system for its auditorium. The primary fund-raising event is a dance at which the famous disc jockey, John Henry will play funky hip-hop and not so funky hip-hop dance tunes. Mr Bishop, the music and theater instructor, has been given the responsibility for coordinating the fund-raising efforts. This is Bishop’s first experience with fund-raising.

Bishop had 500 unnumbered tickets printed for the dance. He left the tickets in a box on his desk and told the choir students to take as many tickets as they thought they could sell for $10 each. In order to ensure that no extra tickets would be floating around, he told them to dispose of any unsold tickets. When the students received payment for the tickets, they were to bring the cash back to Mr. Bishop, and he would put it in a locked box in his desk drawer.

Some of the students were responsible for decorating the gymnasium for the dance. Mr. Bishop gave each of them a key to the money box and told them that if they took the money out to purchase materials, they should put a note in the box saying how much they took and what it was used for.

After 2 weeks the money box appeared to be getting full, so Mr. Bishop asked Luke Wilson to count the money, prepare a deposit slip, and deposit the money in a bank account that he had opened for this fundraising event. On the day of the dance, Bishop wrote a check from the account to pay the DJ, however the DJ said that he accepted only cash and did not give receipts. So Bishop took $ 500 out of the cash box and gave it to him. At the dance Bishop saw Sally working at the entrance to the gymnasium, collecting ticket from the students and selling tickets to those who had not pre-purchased them. Bishop estimated that 400 students attended the dance.

The following day Bishop closed out the bank account, which had $450 in it, and gave that amount plus the $ 300 in the cash box to the Principal of the school. He seemed surprised that after generating roughly $ 4000 in sales, the dance netted only $ 750 in cash. Bishop did not know how to respond.

Required:

1. List the internal controls that were ignored by Mr. Bishop during this fundraiser. (There are at least six)

2. Create an internal control policy that will provide all needed guidelines for the School to follow for every subsequent fundraiser.

3. Do you believe that the Principal should investigate whether fraud has occurred by Mr. Bishop?

4. Do you believe the students have committed fraud?

5. Who could help this principal develop the proper policy and controls?

At a large university it is known that 45% of the students live on campus. The director of student life is going to take a random sample of 100 students. What is the probability that more than half of the sampled students live on campus?

It is known that​ 35% of students change their major in college. In a random sample of

500​ students, what is the probability that less than​ 36% of these students will change their

​major?

A.

0.6808

B.

0.3192

C.

0.0176

D.

0.2000

I believe that the population proportion of Elementary students in Texas who ride the bus to school is more than the population proportion of Elementary students in Oklahoma. In two independent polls I found that 659 of 3502 students ride the bus in Texas and 476 of 3201 students in Oklahoma ride the bus to school. Assume a random sample. Calculate a 90% confidence interval of the two proportions.

You are testing the claim that the mean GPA of night students is different than the mean GPA of day students.

You sample 40 night students, and the sample mean GPA is 2.28 with a standard deviation of 0.56

You sample 30 day students, and the sample mean GPA is 2.13 with a standard deviation of 0.87

Calculate the test statistic, rounded to 2 decimal places

In some states, high school students must pass a graduation test before they are able to receive their high school diplomas. Suppose the students are given up to three chances to pass the exam. If they pass it, they don't need to take it again. If they do not pass the test on the first try, they take it a second time. If they don't pass on the second try, they take it a third time. From past data, we know that 78% of students pass the test the first time, while 85% of students who take it a second time pass on the second try, and 60% of students who take it a third time pass on the third try.

a) What percent of students are not allowed to graduate because of their performance on the exam? Enter your answer as a percent, rounded to the nearest tenth of a percent

b) What percent of students take the test three times? Enter your answer as a percent, rounded to the nearest tenth of a percent

c) What percent of students pass a graduation test and receive their high school diplomas? Enter your answer as a percent, rounded to the nearest tenth of a percent.