Assume that a diagnostic test for COVID-19 has 95% accuracy and 40% of all people in a population have COVID-19. Make a tree diagram for this problem. What is the probability that the result of a test in this population is positive? If a person's test in this population is positive, what is the probability that they have the disease? Use 2 decimal places.

A consumer group plans a comparative study of the mean life of four different brands of batteries. Ten batteries of each brand will be randomly selected and the time until the energy level falls below a pre-specified level is measured.

Dandelions have effects on crop production and lawn growth and are studied. In one region, the mean number of dandelions per square meter was found to be 10.8.Find the probability of no dandelions in an area of 1 m².P(X=0)=P(X=0)= Find the probability of at least one dandelion in an area of 1 m².P(at least one) = Find the probability of at most two dandelions in an area of 1 m².P(X≤2)=P(X≤2)=

The level of nitrogen oxides (NOX) and nonmethane organic gas (NMOG) in the exhaust over the useful life (150,000150,000 miles of driving) of cars of a particular model varies Normally with mean 8080 mg/mi and standard deviation 66 mg/mi. A company has 1616 cars of this model in its fleet. Using Table A, find the level ?L such that the probability that the average NOX + NMOG level ?¯x¯ for the fleet greater than ?L is only 0.030.03 ? (Enter your answer rounded to three decimal places. If you are using CrunchIt, adjust the default precision under Preferences as necessary. See the instructional video on how to adjust precision settings.)

Section 9.4 5.) A die is tossed 120 times. Use the normal curve approximation to the binomial distribution to find the probability of getting the following result. Exactly 17 5's Use the table of areas under the standard normal curve given below Click here to page 1  Click here to view page 2  Click here to view page 3 Click here to page 4   Click here to view page 5   Click here to view page 6

On each trial of an experiment, a participant is presented with a constant soft noise, which is interrupted at some unpredictable time by a slightly louder sound. The time it takes for the participant to react to the louder sound is recorded. The following list contains the reaction times (in milliseconds) for 7 trials of this experiment. 541, 800, 667, 362, 542, 667, 800 Send data to calculator (a) What is the median of this data set? If your answer is not an integer, round your answer to one decimal place. 1 2 (b) What is the mean of this data set? If your answer is not an integer, round your answer to one decimal place. (c) How many modes does the data set have, and what are their values? Indicate the number of modes by clicking in the appropriate circle, and then indicate the value(s) of the mode(s), if applicable. zero modes one mode: 0 O two modes: and ?