1. What is the two’s complement of: 00110101

2. Carry out the following calculation using 8-bit signed arithmetic (convert to 8-bit binary sequences) and use two’s complement for the negative number, give the result as both an 8-bit binary sequence and in base 10: 127 – 74.

3. What does shifting a binary sequence to left by 3 places correspond to (from the arithmetic standpoint)

Number Analysis Program Python:

Initialize an array with these specific 20 numbers: 26 45 56 12 78 74 39 22 5 90 87 32 28 11 93 62 79 53 22 51

Display the following data:

1. The lowest number in the list
2. The highest number in the list
3. The total of the numbers in the list
4. The average of the numbers in the list

QUESTION 12

1. A teacher would like to estimate the mean grade for her class of 50 students on the most recent exam. After the first 10 tests are graded (in random order), her sample results are as follows:

   45 60 74 75 79 80 85 86 90 96

   Which of the numbers below represent the point estimate?

   	A.	15.4
   	B.	77.0
   	C.	84.0
   	D.	79.5

LITTLE’S LAW: Diant grocery stores wish to estimate time customers spend, on average, in store and in a checkout line. The results of the data collected are as below:

Avg. rate of customers entering store = 300 cust/hr

Avg. # of customers in store = 150 cust

% of customers who do not make a purchase = 5%

Avg. # customers in checkout lanes = 28.5 cust

a) How much time does the average customer spend in the store?

b) How much total time is spent, on average, to check out? Hint: This is the time that is spent in the checkout lane.

An investigation of past consumer surveys done by a company reveals that 2/3 of customers contacted respond to the survey. The marketing manager wants to do a new survey and plans to contact 198 customers.

(a) How many responses should the manager expect to receive?

(b) Give an approximation of the probability that 140 or more customers will respond.

(c) Give an approximation of the probability that 135 to 150 customers will respond.

(d) Give an approximation of the probability that 130 or less customers will respond.

(e) Compare your approximate answers with the exact probability values obtained on Excel.

A test of abstract reasoning is given to a sample of students before and after they completed a formal logic course. Assume that two dependent samples have been randomly selected from normally distributed populations. The results are given below. At the 0.05 significance level, use critical value method to test the claim that the mean score is not affected by the course. Does the course improve the students’ skill on abstract reasoning?

     Before 74 83 75 88 84 63 93 84 91 77

     After 73 77 70 77 74 67 95 83 84 75

1. State the requirement
2. State the null and alternative hypotheses with the correct symbols
3. Write all the statistics
4. Write the formula of the test statistic and find the test statistic (you may use a calculator, but you are required to write down the command and all the numbers you enter)
5. Find the critical value or the P-value (you may use a calculator, but you are required to write down the command and all the numbers you enter)
6. Decide to reject or fail to reject H₀ and explain the reason
7. Wording the conclusion
8. Answer the question based on your result above

Emery Pharmaceutical uses an unstable chemical compound that must be

kept in an environment where both temperature and humidity can be controlled.

Emery uses 200 pounds per month of the chemical, estimates the holding cost to be

£3.33 (because of spoilage), and estimates order costs to be £10 per order. The cost

schedules of two suppliers are as follows:

Vendor 1 Vendor 2 Quantity Price/LB (£) Quantity Price/LB (£) 1-49 35.00 1-74 34.75 50-74 34.75 75-149 34.00 75-149 33.55 150-299 32.80 150-299 32.35 300-499 31.60 300-499 31.15 500+ 30.50

500+ 30.75

Vendor 3 Vendor 4 Quantity Price/LB (£) Quantity Price/LB (£) 1-99 34.50 1-199 34.25 100-199 33.75 200-399 33.00 200-399 32.50 400+ 31.00

400+ 31.10

a) What quantity should be ordered, and which supplier should be used?

b) Discuss factor(s) should be considered besides total cost.

Please with explanations

(Heights of Presidents since 1900) Listed below are the heights (in inches) of the Presidents who started serving in 20th until today. Assume that these values are sample data from some larger population.

67, 70, 72, 71, 72, 70, 71, 74, 69, 70.5, 72,

75, 71.5,   69.5, 73, 74, 74.5, 71.5, 73.5, 72.5,

(a) Find the mean

(b) Find the median

(c) Find Q₁ and Q₃

(d) Construct a boxplot for the data

(e) Find the range

(f) Find the standard deviation and variance

(g) Assume that the values are sample data, construct a 99% confidence interval to estimate of the population mean

(h) Assume that the values are sample data, construct a 99% confidence interval fro the population standard deviation

(i) The mean height of men is 69.0 inches. Use a 0.05 significance level to test the claim that this sample comes from a population with a mean greater than 69.0 inches. Do Presidents appear to be taller than a typical man in U. S.? (Show hypothesis test details, test statistic, decision making, and conclusion)

7. Identify the three sources of contraction in a metal casting after pouring. 8. What is directional solidification and what is chill in casting? 9. Total solidification time is defined as (select one): (a) time between pouring and complete solidification, (b) time between pouring and cooling to room temperature, (c) time between solidification and cooling to room temperature, (d) time to give up the heat of fusion? 10. What is the difference between a pattern and a core in making sand casting mould? 11. What is function of riser? 12. What properties determine the quality of a sand mould for sand casting?