Suppose that a dart board is given by a circle of radius 1 in R², centered at (0,0). You throw a dart at the dart board, and the position that it lands is given by a pair of random variables, (X, Y). a. Suppose that the probability of a "Bull's Eye" is zero; that is, P(X = 0, y = 0) = 0.
b. Prove that there must be some integer n > 0 such that P (√X^2 +Y^2 > 1/2) > 0.

Jeffery conducted a survey in his school and found that 30 of the 50 eighth grade students' favorite subject is mathematics. based on the results, jeffery concluded that out of the 200 students in his school, 120 students' favorite subject is mathematics. select the statement that is true about jeffery's conclusion. a. jeffery's conclusion is not valid because the sample was biased since only 200 students were surveyed. b. jeffery's conclusion is valid because the sample was random since all of the students were eighth grade students. c. jeffery's conclusion is valid because the sample was random. d. jeffery's conclusion is not valid because the sample was biased since all of the students were eighth grade students.

What is the range? can’t seem to find it out

The mean of 10 values is 19. if further 5 values areincluded the mean becomes 20. what is the meanthese five additional values? a) 10b) 15c) 11d) 22