Both of these formulas were found on page 225 in Mathematics in Our World (Bluman, 2005). Problem #37 • This sequence is geometric • Ending balance is $814.45 STEPS/CALCULTATIONS YOU PERFORMED TO REACH THE ANSWER: To find the ending balance, the formula of An = a1(rn-1) will be used. The initial balance is $500, the interest is 5%, and the time span is 10 years. 5% will be listed as 1.05 as the initial balance is 100% plus 5% interest, so 105% is written 1.05. The number of terms is n=10, the first term is a1=525, the common ratio is r = 1.05.
Rochelle decided to compare two plants for 50 days, Memphis plant-which will have the vector drive and Birmingham plant-which will use the existing system and prepare a report. The financial analysts believe that the purchase can be justified if the equipment leads to the average increase in production of atleast 10,000 bricks per day. Since we have to check whether the difference between the mean value of the bricks per day at Memphis plant and Birmingham plant is greater than 10000(for purchase to be justified), we will use hypothesis testing for means and compare the sampling distribution of the mean value of bricks produced in a day. This method is the typical method to solve these kind of problems. Data available is Plant Total Bricks produced in 50 days S (standard deviation) x̄ (mean) Memphis 7484500 3402.46 149690 Birmingham 6902350 3364.68 138047 Hypothesis test In a hypothesis test we assume Ho to be true and try to find evidence that shows otherwise.
AP Statistics Name _______________ 3/24/09 Wood/Myers Period _____ Test #12 (Chapter 13) Honor Pledge __________ Part I - Multiple Choice (Questions 1-10) – Circle the letter of the answer of your choice. 1. An SRS of size 100 is taken from a population having proportion 0.8 successes. An independent SRS of size 400 is taken from a population having proportion 0.5 successes. The sampling distribution for the difference in sample proportions has what standard deviation?
The goal of this analysis is to use statistical methodology to predict sales at 2 potential locations at a much more accurate level and determine which location is likely to have higher sales. Data The data used in this analysis comes from census information in the stores’ trading zones as well as data on individual stores. Variables from the most recent census were compiled for the trading zone of each of the 250 stores. For each store there is data gathered on demographics and economics of the trading zones, as well as size, composition and sales of the store. There are a total of 28 quantitative demographic variables each measured as a percentage of the population within the trading zone, 2 quantitative store variables including sales and square feet, and 7 quantitative categorical variables for competitive type.
p.286. no 10.- Two hundred draws will be made at random with replacement from the box -3, -2, -1, 0, 1, 2, 3 (a) If the sum of the 200 numbers drawn is 30, what is their average? (b) If the sum of the 200 numbers drawn is –20, what is their average? (c) In general, how can you figure the average of the 200 draws, if you are told their sum? (d) There are two alternatives: (i) Winning $1 if the sum of the 200 numbers drawn is between –5 and +5 6 Winning $1 if the average of the 200 numbers drawn is between –0.025 and +0.025.
Standard costing also helps managers set target level performance and standards as well as sales prices of products. 2. Based on the purchase of 220,000 square yards of material and a difference of 25 cents from the actual price of $8.25 and standard price $8 leads to an unfavorable price variance of $55,000. As for the difference between the actual 110,000 material used and the 120,000 budgeted, once the budgeted $8 price is factored in we find a favorable quantity variance of $80,000.Finally the difference between an unfavorable $55,000 and favorable $80,000 we have a $25,000 favorable flexible budget variance. 3.
The first class in a relative frequency table is 50–59 and the corresponding relative frequency is 0.2. What does the 0.2 value indicate? Answer: ____Convert 0.2 to a % by times by 100. So 0.2 = 20%, so 20% of the data is between 50 and 59______________ 3. When you add the values 3, 5, 8, 12, and 20 and then divide by the number of values, the result is 9.6.
To find the mean of the sample data set the formula must be used: Sample mean x̄ = (∑x)/N = 446.1/30= 14.87 According to Larson and Farber, 2009, the median of a data set is the value that lie in the middle of the data when the data set is ordered. The given numbers in the table are in order, there are thirty entries (an even number). The median is the mean of the two middle entries. Median = (14.8+14.8)/2 = 14.8 According to Larson and Farber, 2009, the standard deviation is the difference between the entry data and the entry mean. Sample standard deviation x=√(∑(x-µ)^2 )/(N-1) = √8.783/(30-1) = √0.302862 = 0.5503 Construct a 95% Confidence Interval for the ounces in the bottles.
(a) Find a 99% confidence interval for the true mean heart rate of all people with this untreated condition. Show your calculations. (b) Interpret this confidence interval and write a sentence that explains it. 23. Determine the minimum required sample size if you want to be 80% confident that the sample mean is within 2 units of the population mean given sigma = 9.4.
Like the Income variable the Credit Balance variable is also a quantitative variable. With the sample data provided one was able to compute the following calculations. Data Calculations: | | | | Median | 4090 | | | Mode | 3890 | | | Mean | 3964.06 | | | Standard Deviation | 933.4941 | | | Total Sample Variance | 871411.2 | | | Maximum | 5678 | | | Minimum | 1864 | | | Range | 3814 | | | Class width | 476.75 | rounded :500 | In the process of analysing the data one drafted a frequency distribution table which included a total of 8 classes. The frequency for each class was developed along with the calculation of the classes’ midpoint. Taking this information a Histogram bar graph was created.