Let the random variables x and y have joint distribution f(x, y) = (2x + y)/30, x = 1,2 ; y = 1,2,3. a)find the marginal pdf's f1(x) of x and f2(y) of y. b)are x and y independent? justify your answer.

Use the distance formula to determine the distance that point q is from r on the hypotenusebased on a 2-3 ratio.i need asap !

The number of chocolate chips in an 18-ounce bag of chocolate chip cookies is approximately normally distributed with a mean of 1252 chips and standard deviation 129 chips. (a) what is the probability that a randomly selected bag contains between 1100 and 1500 chocolate chips, inclusive? (b) what is the probability that a randomly selected bag contains fewer than 1125 chocolate chips? (c) what proportion of bags contains more than 1225 chocolate chips? (d) what is the percentile rank of a bag that contains 1425 chocolate chips?

If y varies directly as x2 and y=6 when x=6, find the constant of variation.