Coin Flips
Waiting For It
Adding Up the Wins
Roll of the Die
What a Formula!
100

Let X be a Bernoulli(1/4) random variable. The probability that X is equal to 0.

What is 3/4?
100

The probability that a Geometric(1/4) random variable is equal to 2.

What is 3/16?

100

Let X be a Binomial(3,3/4) random variable. The probability that X is greater than 0.

What is 63/64?

100

Let X be a Discrete Uniform(1,9) random variable. The probability that X is odd.

What is 5/9?

100

The mean of a Poisson(3) random variable.

What is 3?

200

The average value of a Bernoulli(0.317) random variable.

What is 0.317?

200

The probability that a Geometric(1/4) random variable is greater than 2.

What is 

1 - (\frac{1}{4} + \frac{1}{4}\cdot\frac{3}{4}) = \frac{9}{16}

200

Let X be a Binomial(4,1/2) random variable. The probability that X is greater than 2.

What is 5/32?

200

Let X be a Discrete Uniform(2,4) random variable. The expected value \mathbb{E}[2X+1] 

What is 

2\mathbb{E}[X] + 1 = 2\cdot3 + 1 = 7

200

The probability that a Poisson(3) random variable is less than 2.

What is 

4 e^(-3)?

300

Let X be a Bernoulli(1/2) random variable. The value of  \mathbb{E}[X^2] 

What is 1/4?

300

Let X be a Geometric(1/2) random variable. The value of  \mathbb{E}[X^2] 

What is 

\mathbb{Var}[X] + (\mathbb{E][X])^2 

=\frac{1-\frac{1}{2}}{(\frac{1}{2})^2} + (\frac{1}{2})^2 = \frac{9}{4}

300

Let X be Binomial(100,0.1). The value of  Var[2X - 5] 

What is 36?

300

Let X be a Discrete Uniform(51,54) random variable. The variance of X.

What is 15/12?

300

Let X be a Poisson (\lambda)  random variable satisfying  \mathbb{E}[X - 1] = 1 . The value of the parameter  \lambda 

What is 2?

400

Let X be a Bernoulli(2/3) random variable. The value of  \mathbb{E}[3^X] 

What is 7/3?

400

Let X be a Geometric(1/2) random variable. The probability that X is greater than 4, given that we know that X is greater than 2,  \mathbb{P}[X > 4 | X > 2] .

What is 1/4?

400

You play 5 games in a row. The probability that you win a game is 1/2, independently of other games. Let X be the number of wins and  B = \{0,1\} . The conditional PMF of X given that  \{X \in B\}  occurs.

400

Let X be a Discrete Uniform(1,87) random variable and let  B = \{2,3,4\} .
The conditional PMF  P_{X|B}(x)  of X given  \{X \in B\} 

400

Let X be a Poisson(2) random variable. Given that X is less than 3, what is the probability that X is equal to 0?

What is 1/5?