There are 38 students in Ms. Flanigan’s math class and 20 of them are boys. If a student is selected at random, what is the probability that a girl is selected? Give your answer as a fraction in simplest form.

Suppose a man is heterozygous for heterochromia, an autosomal dominant disorder which causes two different‑colored eyes in an individual, produced 25‑offspring with his normal‑eyed wife. of their children, 15 were heterochromatic and 10 were‑normal. calculate the chi‑square value for this observation.

Logan wants to know how many skateboards have defective parts. he inspects 20,000 skateboards and keeps track of the number of defects per board. use his probability distribution table to find the expected value for defects on a skateboard.

Are triangles the congruent? write the congruency statement. what is the congruency that proves they are congruent? what is the perimeter of ∆pqr?