In: Statistics and Probability
Suppose a newspaper article states that the distribution of auto insurance premiums for residents of California is approximately normal with a mean of 1525. The article also states that 20% of California residents pay more than 1875.
1. What is the Z score that corresponds to the top 20% (or the 80?ℎth percentile) of the standard normal distribution? Round your answer to 4 decimal places.
2. What is the mean insurance cost?
3. What is the cutoff for the 80?ℎth percentile?
4. Identify the standard deviation of insurance premiums in LA.
Round your answer to two decimal places.
Hint: Use the information from the first 3 questions in this
problem and the formula for finding the z-score.