A motorboat travels 222 miles in 6 hours going upstream. It travels 282 miles going downstream in the same amount of time. What is the rate of the boat in still water and what is the rate of the current?

Aproduction manager test 10 toothbrushes and finds that their mean lifetime is 450 hours. she then design sales package of this type of toothbrush. it states that the customers can expect the toothbrush to last approximately 460 hours. this is an example of what phase of inferential statistics