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determine the are of Z=2
Not all visitors to a certain company's website are customers. In fact, the website administrator estimates that about 12% of all visitors to the website are looking for other websites. Assuming that this estimate is correct, find the probability that, in a random sample of 4 visitors to the website, exactly 2 actually are looking for the website.
My golf group plays a game called "team quota". You take a players handicap and subtract it from 36 and that is that players quota. Quota points are awarded- 1 for a bogie, 2 for a par 3 for a birdie and 4 for a eagle. Each team is randomly chosen with handicaps varing from 12 to 25. The best team total wins. A team is comprised of 4 players but some days a team will only have 3 players. If you have 3 groups of 4 and 1 group of 3 does the group of 3 have a better chance of winning? Thank You
The length of life of an instrument produced
by a machine has a normal distribution with a
mean of 12 months and standard deviation of
2 months. Find the probability that an
instrument produced by this machine will last
a) less than 7 months.
b) between 7 and 12 months.
- The probabilities that Peter, Paul and Mary will go for a holiday this Christmas are 0.25, 0.3 and 0.4 respectively. If Peter goes for a holiday, Paul will not go but Mary will have a probability of 0.8 of going. Whether Paul goes or not, it does not affect Mary’s decision. Let x be the number of them going for a holiday this Christmas.
- Find the probability distribution for x.
- What are the mean and standard deviation of x?
HR manager in L&B real-state company is working with finance department in improving the salaries and the following descriptive statistics were obtained. Table (2) Department Mean SD CoefVar Min Q1 Median Q3 Max IQR Skewness Finance 6.052 3.874 64.01 1.630 3.393 (a) 7.500 22.860 4.107 2.00 HR 5.441 3.235 (b) 2.000 3.200 4.100 6.430 21.860 3.230 (C) IT 5.880 3.887 66.10 0.530 3.250 4.630 (d) 24.980 3.550 2.18 Marketing 6.010 3.737 62.18 1.670 3.475 5.000 6.645 22.200 3.170 2.14 Training 6.095 3.719 61.02 1.500 3.330 5.000 7.640 20.000 4.310 2.00 CoefVar stands for coefficient of variation graph (1) The company has hired you to answer the following questions: 1) Find the missing values of (a), (b), (c) and (d). Finance HR IT Marketing Training 25 20 15 10 5 0 Department salary Boxplot of salary |2) Do you think that the salaries in the departments are skewed, justify your answer with proper measure from table (2). 3) Based on the boxplot for the salaries by department in graph (1),
The dataset in the below table represents the 4-month profits (in million $) of real estate company that operates in Egypt over the period of time between 2014-2018. I II III 2014 15.6 20.4 29.4 2015 13.8 23.2 35 2016 17.8 19.4 30.6 2017 21.4 24.8 33.6 2018 18.4 27.2 34.2 Answer the following questions: 1. Find the seasonal indices for the company’s profits and comment on the results. 2. Find the deseasonalized values of company’s profits and compare it to the actual values graphically. Comment on the results. 3. By using the deseasonalized values obtained in (2), determine the simple linear trend equation. And comment on the results. 4. Predict the expected value of company’s profit in summer 2019 which includes the effects of all the components of time series. And comment on the results.
The number of days required for two suppliers to deliver orders is as follows. Supplier A: 11 10 9 10 11 11 10 11 10 10 Supplier B: 8 10 13 7 10 11 10 7 15 12 Where, the average number of days required for supplier A to deliver orders = 1.47 weeks and Standard Deviation = 0.10 week | P a g e 2 1) Which supplier provides more consistent and homogenous delivery times A or B? Justify your answer. 2) Without any calculation, and if the unit of measurement changes to be in hours, will the homogeneity be the same? 3) And do you think the delivery time for each supplier is symmetric. Support your answer with a proper test for skewness. 4) Prove that ∑ (𝑋𝑖 − 𝑋̅) = 0 𝑛 𝑖=1 Q
The following data represent the time (in minutes) recorded for a sample of 20 employees in order to get to work using public transportation. 28 29 32 37 33 25 29 32 41 34 29 31 33 32 34 30 31 32 35 33 1) Does the sample contain any extreme values? Justify your answer with a suitable test. Comment on the results 2) According to your conclusion in part (1), calculate the best central and the best absolute dispersion measure. 3) Comment on the results obtained in part (2). 4) Without any calculation, if all values are multiplied by 10 minutes, will the location measures and outlier existence be the same? Justify your answer.
Patients (20) with high blood pressure were randomly assigned into two groups, a placebo group and a treatment group. The placebo group received conventional treatment while the treatment group received a new drug that is expected to lower blood pressure. After treatment for a couple of months, blood pressures of the patients were measured.
Determine if the new drug had a significant effect on high blood pressure.
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Blood Pressure (systolic)
Placebo Group New Drug Group
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90 71
95 79
67 69
120 98
89 91
92 85
100 89
83 75
79 78
85 80
