A school has 63% girls and 37% boys. If 23% of the girls wear contacts and 42% of the boys wear contacts

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

What is the sum of these mixed numbers 4 2/3+ 3 1/9

What unit of been sure would be appropriate for the volume of a sphere with a radius of 2 meters