70.49 divided by 19 pls help

You flip a fair coin until you see three tails in a row. What is the average number of headsthat you’ll see until gettingTTT?

Verdich [7]

Answer:

14

Step-by-step explanation:

From the given information:

suppose, Y is the number of times a coin is being flipped.

If the coin is flipped for the first time and we get H, then we have:

TTT = $\dfrac{1}{2}(Y+1)$

Afterward, if we get H, then we waste two times plus the probability of this event $\dfrac{1}{4}$ .

Therefore, we have : $\dfrac{1}{4}(Y+2)$

Afterward, if we get H, then we waste three times plus the probability of this event $\dfrac{1}{8}$ .

Therefore, we have : $\dfrac{1}{8}(Y+3)$

If we got T at the third time, then;

T = $\dfrac{1}{8}(3)$

Thus, average number of headsthat you’ll see until gettingTTT can be expressed as:

$= \dfrac{1}{2}(Y+1)+ \dfrac{1}{4}(Y+2)+ \dfrac{1}{8}(Y+3)+ \dfrac{1}{8}(3)$

= 14

7 0

3 years ago

A teacher records the number of students present in her 1st period class each day. This count is a ___________ random variable.

blagie [28]

This count is a discrete random variable (option A).

<h3>What is a discrete random variable?</h3>

A discrete random variable is a variable that contains integers that can only be a limited number of possible values. A discrete random variable is can contain only a finite set of numbers .

An example of discrete random variable is the number of students in the first period class. It is impossible for the number of students in the class to go on indefinitely.

Discrete random variable has the following properties: