A test is conducted on 25 lemon trees of the same species to
compare two fertilizers, A and B. A sample of 13 lemon trees
randomly selected from the group are given fertilizer A and the
remaining trees are given fertilizer B. From observations made over
a three-week period, the average fruits produced by each lemon tree
is recorded below:
Lemon Fruit Yield (for each tree)
fertilizer A (x1) 44 44 56 46 47 38 58 53 49 35 46 30 41
fertilizer B (x2) 35 47 55 29 40 39 32 41 42 57 51 39
Assume these two samples come from independent normally distributed
populations.
6) Find the mean number of lemons for fertilizer A rounded to the tenths place.
7) Find the mean number of lemons for fertilizer A rounded to the tenths place.
Now perform the two-sample t-test to investigate the evidence of a difference in true mean lemon yields for the two fertilizers.
8) Using a pooled variance, find the p-value.
9) Which of the following hypotheses are most appropriate in determining whether there is a difference in the true mean lemon yields for the two fertilizers? (Choose 2)
Ho: μ1 = μ2
Ho: μ1 ≠ μ2
Ha: μ1 = μ2
Ha: μ1 ≠ μ2
Ho: μ1 > μ2
Ho: μ1< μ2
Ha: μ1 > μ2
Ha: μ1 < μ2
In: Statistics and Probability
In: Accounting
A company wants to determine whether its consumer product ratings
(0minus−10)
have changed from last year to this year. The table below shows the company's product ratings from eight consumers for last year and this year. At
alphaαequals=0.05,
is there enough evidence to conclude that the ratings have changed? Assume the samples are random and dependent, and the population is normally distributed. Complete parts (a) through (f).
|
Consumer |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
|
|
Rating left parenthesis last year right parenthesisRating (last year) |
55 |
55 |
44 |
22 |
66 |
88 |
55 |
77 |
|
|
Rating (this year) |
44 |
55 |
66 |
22 |
55 |
1010 |
88 |
99 |
In: Statistics and Probability
Q1. Compressors powered by natural gas engines are increasing in popularity. Several major manufacturing facilities have already replaced the electric motors that drive their compressors with gas-driven engines in order to reduce their energy bills since the cost of natural gas is much lower than the cost of electricity. Consider a facility that has a 130-kW compressor that runs 4400 h/yr at an average load factor of 0.6. Making reasonable assumptions and using unit costs for natural gas and electricity at your location, determine the potential cost savings per year by switching to gas-driven engines. (TOTAL 25 MARKS)
In: Physics
Is HDTV ownership related to quantity of purchases of other
electronics? A Best Buy retail outlet collected the following data
for a random sample of its recent customers. At α = 0.10,
is the frequency of in-store purchases independent of the number of
large-screen HDTVs owned (defined as 50 inches or more)?
| In-Store Purchases Last Month | |||||||||||||||
| HDTVs Owned | None | One | More Than One | Row Total | |||||||||||
| None | 14 | 15 | 12 | 41 | |||||||||||
| One | 17 | 33 | 30 | 80 | |||||||||||
| Two or More | 19 | 40 | 63 | 122 | |||||||||||
| Col Total | 50 | 88 | 105 | 243 | |||||||||||
Calculate the chi-square test statistic, degrees of freedom, and the p-value.
In: Statistics and Probability
Using Python provide the implementation of a function called
"isAdjacent" that accepts a string.
The function checks if two adjacent characters in the string are
the same; if they are the same, then return True otherwise return
False. The function should ignore case and check for
non-empty string. If it's an empty string, then return
the message 'Empty string'.
Sample runs:
print( isAdjacent('ApPle')) # True
print( isAdjacent('Python')) # False
print( isAdjacent('')) # Empty string
In: Computer Science
Jim is a transportation engineer and is interested in whether roadways that score high in one traffic engineering aspect also tend to score high in other aspects. To address this question, he completed a survey of 80 roadways that contain five measures of effectiveness with ratings for safety, capacity, speed, alignment, and flow.
a) Conduct a correlational analysis to investigate these relationships. What are your conclusions?
b) Jim determines that the speed of a facility affect/s the other roadway scores. Reevaluate Jim's hypothesis by controlling for speed. What effect does partialling out the effects of speed have on the relationships?
safety capacity speed alignment flow
48 56 48 35
47
44 50 47 41
51
38 41 49 59
46
48 59 59 49
52
44 44 52 37
47
43 57 42 52
54
49 53 56 32
49
52 65 57 54
54
55 63 56 58
53
50 60 49 52
54
45 47 44 51
49
61 56 57 63
50
49 57 50 51
50
44 45 46 31
47
39 50 51 28
52
50 51 51 43
54
49 51 50 50
49
37 52 44 45
53
49 55 51 47
53
47 48 46 44
54
55 56 55 42
54
49 60 62 58
53
45 58 65 59
54
39 40 36 44
46
54 56 51 55
52
58 58 51 44
53
52 52 62 47
53
50 56 38 47
51
62 57 52 25
53
55 55 59 57
49
50 52 52 47
53
44 35 44 46
45
55 55 39 24
48
46 45 44 54
47
48 51 47 50
50
52 52 38 53
47
52 49 50 59
49
50 49 39 40
48
48 50 52 52
43
50 45 46 36
47
50 46 44 44
52
43 40 43 27
45
40 44 54 50
47
57 67 53 41
58
57 52 56 67
58
61 62 51 60
56
46 52 52 60
56
42 44 48 41
56
60 58 66 50
57
47 47 58 51
56
50 59 51 43
57
63 65 56 63
62
59 52 42 42
56
50 52 59 57
56
49 59 62 51
61
51 52 56 44
58
47 62 67 54
66
52 62 58 47
62
60 48 55 45
63
45 45 59 47
60
59 53 51 39
57
57 51 68 59
59
46 60 64 54
57
51 61 46 44
59
47 53 49 41
55
50 63 52 48
64
57 69 70 51
57
50 57 51 37
56
65 69 62 60
55
50 58 54 49
56
56 63 54 49
58
54 65 57 38
56
42 53 47 45
56
53 53 62 49
59
61 54 57 63
61
47 56 50 58
55
46 55 48 55
57
57 54 58 58
57
56 60 51 47
58
50 52 50 46 56
In: Statistics and Probability
1. The Pratt Corporation manufactures computer terminals. The following data give the number of computer terminals produced at the company for a sample of 30 days. 24 32 27 23 33 33 29 23 28 25 21 26 31 22 27 33 27 28 29 23 31 35 34 22 26 28 23 31 27 35 Make a frequency table showing class boundaries, class midpoints, frequencies, relative frequencies, and cumulative frequencies. What is the modal class?
2. The following date give the weight (in pounds) lost by 16 new members of a health club at the end of their first two months of membership. 5 10 8 7 25 12 6 14 11 10 21 9 8 11 18 11 Find a. Mean b. Median c. Mode
3. The following data give the weekly dinner expenditures for a sample of five students. $62 96 45 55 72 a. Find the range b. Find the sample mean. c. Find the sample variance d. Find the sample standard deviation. e. Find the CV
4. The following data give the hours worked last week by 30 employees of a company. 42 45 40 38 35 47 40 27 39 43 40 53 23 51 42 48 40 36 51 40 48 34 21 40 31 34 16 39 41 36 Give the five-number summary including the low value, Q , Median, Q and high value. Find the interquartile range and check for outliers.
5. The following are the scores of 30 college students on a statistics test. 75 52 80 96 65 79 71 87 93 95 69 72 81 61 76 86 79 68 50 92 83 84 77 64 71 87 72 92 57 98 Make a stem-and-leaf display of the data.
In: Statistics and Probability
Company X produces an end product Afor the market. One unit of
Ais made by assembling 1 unit of K, 2 units of L, and 1 unit of M.
One unit of K is made of 2 units of G and 3 units of H; one unit of
L is assembled using 1 unit of M and 2 units of N. Current on-hand
inventories for L and M are 130 and 60, respectively. Scheduled
receipts are 300 for L at the beginning of week 1 and 150 for M at
the beginning of week 2.
Lead times for K and L are one week, and lead times for other
components are two weeks. The final assembly time for A is one
week.
1. Fill in Table 1 to prepare a master production schedule for end
product Ausing a fixed lot size of 200. The beginning inventory for
A is 180; the forecast and committed customer orders
for A are provided in this table.
| Week | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
| Forecast | 80 | 70 | 50 | 70 | 80 | 65 | 90 | 100 |
| Customer orders (committed) | 85 | 20 | 30 | 20 | ||||
| Projected on-hand inventory | ||||||||
| MPS Receipt | ||||||||
| MPS Start | ||||||||
| Available-to-promise inventory (uncommitted) |
Table 1: MPS table for end product A in Question 1
b. Construct the product structure tree (i.e., the BOM chart) for A.
c. Use your master production schedule in Table 1 to develop a material requirement plan (MRP) for the subassembly L using the lot-for-lot policy.
| Week | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
| MPS Start for A |
| L |
Lead time: 1 week; On hand 130; Scheduled Receipt in week 1: 300 |
|||||||
| Gross Requirement | ||||||||
| Scheduled Receipts | ||||||||
| Projected On Hand | ||||||||
| Net Requirement | ||||||||
| PO Receipts | ||||||||
| PO Releases | ||||||||
Thanks very much
In: Operations Management
16. A 1.8-kg projectile is fired from level ground. The vertical component of the initial velocity is 80 m/s and the horizontal component is 16 m/s. Ignore air resistance and the curvature of the earth in this problem. How far in meters does the projectile travel horizontally?
19. If one platter of lasagna uses 1.5 cups of tomato sauce, how many cups of tomato sauce will 4 platters of lasagna require?
20. A sprinter runs 53 meters in 7 seconds. What is his average speed?
In: Physics