(a) Let X be the number of tosses until you get the first head. What's EX and Var(X)? (No need to prove.) (b) Let Y be the number of tosses until you get 10 heads. Write the probability of Y = k. Here k ≥ 10 is a positive integer. (c) Compute EY and Var(Y). (Hint: Using the property of independence will be much easier than calculating by definition.)

(a) Let X be the number of tosses until you get the first head. What's EX and Var(X)? (No need to prove.) (b) Let Y be the number of tosses until you get 10 heads. Write the probability of Y = k. Here k ≥ 10 is a positive integer. (c) Compute EY and Var(Y). (Hint: Using the property of independence will be much easier than calculating by definition.)

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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