The average number of miles (in thousands) that a car's tire will function before needing replacement is 66 and the standard deviation is 11. Suppose that 43 randomly selected tires are tested. Round all answers to 4 decimal places where possible and assume a normal distribution. Is the assumption that the distribution is normal necessary? For the 43 tires tested, find the probability that the average miles (in thousands) before the need for replacement is between 68.4 and 70.2
A. The average number of miles (in thousands) that a car's tire will
- For the 43 tires tested, find the probability that the average miles (in thousands) before the need for replacement is between 68.4 and 70.2
B. CNNBC recently reported that the mean annual cost of auto insurance is 1050 dollars. Assume the standard deviation is 230 dollars, and the cost is
1.A simple random sample of 17 auto insurance policies, find the probability that the average cost is more than $1065
C. Suppose the age that children learn to walk is normally distributed with mean 13 months and standard deviation 1.4 month. 17 randomly selected people were asked what age they learned to walk. Round all answers to 4 decimal places where possible. Is the assumption that the distribution is normal necessary?
- For the 17 people, find the probability that the average age that they learned to walk is between 11.5 and 14.5 months old.
Trending now
This is a popular solution!
Step by step
Solved in 3 steps with 1 images
