A fair six-sided die is rolled. What is the expected value of the roll?
3.5
3
2.5
4
A random number generator produces a uniform distribution between 0 and 1. What is the probability that the generated number is greater than 0.7?
0.7
1
0.5
0.3
What does the expected value (mean) of a random variable represent?
The average of all possible values, weighted by their probabilities.
The spread or dispersion of the variable's values.
The probability of the variable taking on a specific value.
The most frequent value the variable takes on.
In a standard deck of 52 cards, you draw one card. What is the probability of drawing a heart or a spade?
1/13
1/2
1/52
1/4
A random variable X has a probability distribution as follows: P(X=0) = 0.2, P(X=1) = 0.3, P(X=2) = 0.5. What is the expected value of X?
1.5
1.2
A random variable representing the number of website visitors in an hour is an example of what type of variable?
Discrete
Ordinal
Continuous
Qualitative
Which of the following is NOT a valid probability value?
0
0.75
1.25
If you roll a fair six-sided die, what is the probability of rolling a 3 OR an even number?
1/6
1/3
2/3
A random variable X follows a uniform distribution between 0 and 10. What is the probability that X is greater than 7?
0.2
0.1
A fair coin is tossed three times. What is the probability of getting exactly two heads?
3/8
1/8