Among fatal plane crashes that occurred during the past 50 years, 668 were due to pilot error, 57 were due to other human error, 628 were due to weather, 449 were due to mechanical problems, and 325 were due to sabotage. Construct the relative frequency distribution. What is the most serious threat to aviation safety, and can anything be done about it? Cause Frequency Plot error Other human error Weather Mechanical problems Sabotage (Round to one decimal place as needed.) CL

A biologist exposed a certain type of bacteria to gamma radiation to see how long they would live. He gathered data on the survival time of a number of bacterial cells and organized the data into the histogram below. Use the histogram to construct a frequency table. (The relative frequencies should be in decimal form.) 60+ 50 40 30 10 440 282 Survival Time (in Seconds) 45 124 203 361 519 Survival Time of Bacteria upon Exposure to Gamma Radiation Frequency Survival Time (in Seconds) Relative Frequency 45-124 124-203 203-282 282-361 361-440 440-519 Frequency 20

Questions: a,b,c

Answer these two math questions

Problems Calculate the answer to each problem. You may use your calculator. Show some work. 14. Consider the following data showing a sample of 20 car speeds (in mph) on Route 24. First is the raw data, then a frequency distribution in which the bins have been determined but have not yet been filled in. 57 60 62 63 65 65 65 67 68 70 72 74 75 78 79 81 84 86 91 98 Speed (mph) 50-59 60-69 70-79 80-89 90-99 Frequency 1 Relative freq. 5% a) The first column has been filled in as an example. Fill in the rest of the columns, both the frequency and relative frequency. Express the relative frequency as a percent. b) Sketch the relative frequency histogram for this data. symmetric skewed left skewed right c) Circle the shape of this histogram: d) Find the range. e) Find the mode. f) Find the median. g) Find the mean. h) Note that the mean is larger than the median. Why is that?

Question 9

A randomly selelected group of individuals were asked how many marbles they believed were contained in a sealed jar. The following frequency distribution summarizes the results. Complete the table by determining the midpoints, relative frequencies, and cumulative frequencies. You may answer using decimals to three places when necessary  Marbles   Frequency   Midpoints   Relative Frequency   Cumulative Frequency  180 - 194 12       195 - 209 4       210 - 224 10       225 - 239 3       240 - 254 9       What is the class width of this frequency distribution?

Can you fill the table according to data? Thank you!

1. Find the class midpoints of the first three classes (20-29,30-39, and 40-49) 2. Is the data displayed in the frequency table approximately normal? Explain your reasoning

how can i tell is a frequency table is skewed