df= Critical t values 35 2.724 2.438 2.030 1.690 1.306 35 36 2.719 2.434 2.028 1.688 1.306 36 Two tails 37 2.715 2.431 2.026 1.687 1.305 37 38 2.712 2.429 2.024 1.686 1.304 38 39 2.708 2.426 2.023 1.685 1.304 39 40 2.704 2.423 2.021 1.684 1.303 40 45 2.690 2.412 2.014 1.679 1.301 45 50 2.678 2.403 2.009 1.676 1.299 50 alues 60 2.660 2.390 2.000 1.671 1.296 60 70 2.648 2.381 1.994 1.667 1.294 70 a/2 a/2 80 2.639 2.374 1.990 1.664 1.292 80 90 2.632 2.368 1.987 1.662 1.291 90 100 2.626 2.364 1.984 1.660 1.290 100 200 2.601 2.345 1.972 1.653 1.286 200 Critical t value (negative) Critical t value 300 2.592 2.339 1.968 1.650 1.284 300 (positive) 400 2.588 2.336 1.966 1.649 1.284 400 500 2.586 2.334 1.965 1.648 1.283 500 1000 2.581 2.330 1.962 1.646 1.282 1000 2000 2.578 2.328 1.961 1.646 1.282 2000 Large 2.576 2.326 1.960 1.645 1.282 Large 03:10 Area in One Tail 0.005 0.01 0.025 0.05 0.10 Degrees of Area in Two Tails Degrees of Freedom 0.01 0.02 0.05 0.10 0.20 Freedom Refer to the accompanying data display that results from a sample of airport data speeds in Mbps. Complete parts (a) through (c) below. Click the icon to view at distribution table. Tinterval (13.046,22.15) x=17.598 Sx=16.01712719 n=50 a. What is the number of degrees of freedom that should be used for finding the critical value ta/2? df= (Type a whole number.) b. Find the critical value ta/2 corresponding to a 95% confidence level. La/2=0 (Round to two decimal places as needed.) c. Give a brief general description of the number of degrees of freedom. OA. The number of degrees of freedom for a collection of sample data is the total number of sample values. OB. The number of degrees of freedom for a collection of sample data is the number of sample values that can vary after certain restrictions have been imposed on all data values. OC. The number of degrees of freedom for a collection of sample data is the number of unique, non-repeated sample values. OD. The number of degrees of freedom for a collection of sample data is the number of sample values that are determined after certain restrictions have been imposed on all data values.

The amount of annual rainfall in a city over the past 100 years follows a normal curve with average of 26 inches and SD of 1.5 inches. Fill in the blank. An annual rainfall of 28.1 inches in 2021 was at the ____th percentile of the rainfall distribution.

state whether the parameter of interest is a mean or a proportion: a survey reports that local t news has shown a 17% increase in revenue within a two year period while newspaper revenues decreased by 6.4% during this time period.

The histogram to the right shows the times between eruptions of a geyser for a sample of 300 eruptions (which means 299 times between eruptions). Over the histogram, draw a smooth curve that captures its general features. Describe the distribution in terms of its number of modes, its symmetry or skewness, and its variation. Chose the correct answer below. Frequency 60- 40 20- OA. three modes, symmetric, wide variation. B. one mode, symmetric, low variation C. two modes, left-skewed, wide variation. OD. one mode, right-skewed, moderate variation 0- 50 60 70 80 90 100110 4 ہے Q Q Q

Identify each quantitative variable as continuous or discrete. Number of students at BCHS that regularly consume caffeinated beverages. Answer 1 Length of time RBHS teachers spend outside of school hours preparing for instruction. Answer 2 Weights of wrestlers on the WKHS Wrestling Team. Answer 3 Ages in years of students at SAHS.

a certain brand produces box with weight of 100 gr.the average weight of 20 samples equals to 102 gram. distribution of the weight of the boxes is 1.25. Conduct a test about the standart weight of the boxes. does the product still weight 100gram or heigher? Write the z value which you should use for comparison.

Determine the Coefficient of Variation of a data set given the x̅= 2.54 and s = .74. Round to the nearest tenth of apercent

The number of cans of soft drinks sold in a machine each week is recorded below. Develop forecasts for the period indicated and error calculations. 155, 145, 155, 162, 180, 165, 172, 149, 170, 172 Exponential smoothing.  Use an alpha level of .8   What is the forecast for week 10? What is the Mean Absolute Error (MAE)?

The average price for one square metre of land is recorded for seven different locations in Melbourne, Australia. The following table shows the average prices for these zoom in 1 the distances from the centre of the Melbourne city. This data is also shown on the scatter diagram below. Distance from city centre, km (x) Price for 1 m² of land, in thousands AUD (y) 1.2 a 3.1 3.3 4.8 5.2 2.4 1.8 1.4 1.3 0.8 2.5 1.5 0.5 1 3 4 6 Distance (km) (a) Use the scatter diagram to find the value of a and b in the table. 15 16 (b) Calculate (i) the mean distance from the Melbourne city centre, ; 17 (ii) the mean 1 m² price, in thousands AUD, ğ; 18 (iii) the Pearson's product-moment correlation coefficient, r. 19 (c) Write down the equation of the regression line y on x. 20 (d) Use the line of the regression equation to estimate the price of 1 m² of the land 4 km from the Melbourne city centre. State whether your estimate is reliable and justify your answer. 21 22 1 m² price (thousand AUD)

Calcium is essential to tree growth because it promotes the formation of wood and maintains cell walls. In 1990, the concentration of calcium in precipitation in a certain area was 0.15 milligrams per liter (mg/L). A random sample of 10 precipitation dates in 2007 results in the following data table. Complete parts (a) through (c) below. Click the icon to view the data table. (a) State the hypotheses for determining if the mean concentration of calcium precipitation has changed since 1990. Но Ho: 0.15 mg/L H1: 0.15 mg/L i Data Table (b) Construct a 95% confidence interval about the sample mean concentration of calcium precipitation. The lower bound is The upper bound is (Round to four decimal places as needed.) 0.237 0.067 0.224 0.126 0.081 0.131 0.075 0.171 0.314 0.091 (c) Does the sample evidence suggest that calcium concentrations have changed since 1990? Print Done A. Yes, because the confidence interval does not contain 0.15 mg/L. B. Yes, because the confidence interval contains…