Eco-Cook steamer has a mean time before failure of 31 months with a standard deviation of 3 months, and the failure times are normally distributed. What should be the warranty period, in months, so that the manufacturer will not have more than 10% of the steamers returned? Round your answer down to the nearest whole number.

In all honesty, there really is no “work” per say to show. mainly it’s just using the process of elimination. the question is asking which domain(s) would be the most appropriate for the function c(n). n is the number of observed vehicles so right away, 1, 2, and 3 can be eliminated.why? 1, 2 start in the negatives and therefore it is impossible to observe negative cars. so, #4 would be the best answer to the given problem.

Ibelieve it's a. 2.2 - x = -10.85 (plz tell me if it's right : ) )

What is your question again i don't understand