A surf shop surveyed 100 customers about the number of items purchased and the length of time spent shopping in the store. Classify the random variables from the survey.

Suppose that x and y are both differentiable functions of t and are related by the given equation. use implicit differentiation with respect to t to determine startfraction dy over dt endfraction in terms of x, y, and startfraction dx over dt endfraction .

If $190 is invested at an interest rate of 11% per year and is compounded continuously, how much will the investment be worth in 4 years? use the continuous compound interest formula: a = pert

Let x have probability generating function gx (s) and let un generating function u(s) of the sequence uo, u1, satisfies p(x > n). show that the (1- s)u(s) = 1 - gx(s), whenever the series defining these generating functions converge.