Which histogram shows a standard deviation of roughly 5? 40 50 60 10 20 30 0 0 10 20 30 40 50 60 A OA OB OC OD 10 15 20 25 30 35 40 9 11 13 15 17 19 21 10 20 30 40 50 60 0 50 30 0 10 B D -5 10 25 40 55 70 85 -60 -40 -20 0 20 40 60

Calcium levels in people are normally distributed with a mean of 9.4 and a standard deviation of 0.4 . Individuals with calcium levels in the bottom 10% dL of the population are considered to have low calcium levels. Find the calcium level that is the borderline between low calcium levels and those not considered low. Carry your intermediate computations to at least four decimal places. Round your answer to one decimal place.

The grades for 20 students on the most recent exam are given in the data table below. Round your answers to 2 decimal places as needed 46 71 41 94 50 47 85 86 98 72 82 40 47 80 44 89 61 66 81 96 Mean = Median = Standard deviation = Minimum score = Highest score =

Please use the information provide in the picture to answer the question in the other picture

The following data represent the high-temperature distribution for a summer month in a city for some of the last 130 years. Treat the data as a population. Complete parts (a) through (c). Temperature Days 50-59 3 60-69 317 70-79 1412 (a) Approximate the mean and standard deviation for temperature. p= (Round to one decimal place as needed.) 80-89 1497 90-99 261 100-109 13

Suppose that a category of world class runners are known to run a marathon (26 miles) in an average of 146 minutes with a standard deviation of 13minutes. Consider 49 of the races.Let X = the average of the 49 races. Find the 60th percentile for the average of these 49 marathons. (Round your answer to two decimal places.)min

Suppose that the speeds of cars travelling on California freeways are normally distributed with a mean of 61 miles tickets for cars with speeds exceeding 80 The records show that exactly 1% of the speeds exceed this limit. Find the standard deviation of the speeds of hour cars travelling on California freeways. Carry your intermediate computations to at least four decimal places. Round your answer to at least one decimal place. miles hour X miles hour 5 . The highway patrol's policy is to issue

Assume that the mean height of men in the United States is 70 inches, with a standard deviation of 3 inches.  A particular man is 80 inches tall.  Find the z-score of his height.  (Round to two decimal places.)

For the past several years, the Philadelphia Fire Departments has been keeping track of the number of fire hydrants that been opened illegally daily during heat waves. These data(rounded to the nearest 10) are given in the table below. Use the information to calculate how many hydrants the department should expect to be opened per day during the upcoming heat wave also find the Standard deviation of number of fire hydrants opened.  Hydrants opened    20     30    40     50    60    70   Days                          14     12     15      11      9      1