If 11x+5y = 9
11x +3y=1

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

Last month, a 770 g box of cereal was sold at a grocery store for $3.10. however, this month, the cereal manufacturer launched the same cereal in a 640 g box, which is being sold at $2.50. what is the percent change in the unit price?

Three people are traveling and need to exchange the currency of their native country for the currency of the country they are visiting. drag each exchange to the category that shows the ratio of currencies in that exchange.