Probably Probability
The complete set of all possible outcomes of an experiment is called this.
What is the sample space?
The variable representing the number of defective items in a box of 20 items is this type of random variable.
What is a discrete random variable?
If P(X ≤ 4) = 0.72, then 0.72 represents this type of probability.
What is a cumulative probability?
A binomial experiment has this number of possible outcomes for each trial.
What are two?
The normal distribution has this general shape
What is a symmetric bell-shaped curve?
When approximating P(X ≤ 10) using a normal distribution, the upper boundary is adjusted to this value.
What is 10.5?
IF the probability of an event is certain, it has this value.
What is 1?
The probabilities assigned to the possible values of a discrete random variable form this.
What is a probability distribution?
The cumulative probability at the largest possible value of X must be this.
What is 1?
In a binomial experiment, the probability of success must remain this from trial to trial.
What is same or constant?
In a normal distribution, the mean, median and mode have this relationship.
What is they are equal?
This correction is used when approximating a discrete distribution with a continuous normal distribution.
What is the continuity correction?
A coin is tossed twice. The probability of obtaining exactly one head is this.
What is 2/4 or 1/2?
If X represents the number of heads obtained when three coins are tossed, these are the possible values of X.
What are 0, 1, 2 and 3?
Given P(X ≤ 8) = 0.91 and P(X ≤ 2) = 0.18, this is P(2 < X ≤ 8).
What is 0.73?
The fourth condition for a binomial experiment, besides fixed trials, two outcomes and constant probability, is this.
What is independent trials?
X ~ N(50, 100). This is P(X > 50).
What is 0.5?
A situation involves 40 independent trials, exactly two outcomes per trial and a constant probability of success. This distribution is the natural model.
What is the binomial distribution?
A student argues that P(A ∩ B) must always equal P(A)P(B). This statement is valid only when the events satisfy this condition.
What is independence?
For a random variable X, If P(X = 2) = 0.30, P(X = 3) = 0.45 and P(X = 4) = 0.25, P(X > 2) is this.
What is 0.70?
For a Random Variable X, a table gives P(X = 0) = 0.15, P(X = 1) = 0.25, P(X = 2) = 0.35. This must be the probability of X = 3 if these are the only possible values.
What is 0.25?
If X ~ Bin(20, 0.30), the variance is this.
What is 4.2?
A distribution has mean 80 and standard deviation 10. This is the score, X, corresponding to z = 1.5.
What is 95?
A binomial distribution has n = 100 and p = 0.2. A student uses a normal approximation without checking suitability. The two quantities that should first be examined are these.
What are np>5 and nq>5?
A class has 40 students. Twenty-four take Mathematics, 18 take Physics and 10 take both. The number who take Mathematics or Physics is this.
What is 32?
A random variable has probabilities 0.15, 0.25, 0.35 and 0.30. The distribution is invalid because of this.
What is that the probabilities sum to 1.05?
A distribution has probabilities 0.10, 0.25, 0.30 and 0.35 for X = 1, 2, 3 and 4. F(3) is this.
What is 0.65?
A machine produces defective items with probability 0.1. For 8 items, the probability of no defective items is approximately this.
What is 0.4305?
A test has μ = 65 and σ = 8. The score corresponding to z = −1 is this.
What is 57?
X ~ Bin(50, 0.4). The appropriate normal approximation has these parameters.
What are μ = 20 and σ² = 12?
A class survey gives P(M) = 0.60, P(I) = 0.45 and P(M ∩ I) = 0.25. The probability that a student takes Mathematics or IT is this.
What is 0.80?
A random variable has E(X) = 4.2 and E(X²) = 20. The variance is this.
What is 2.36?
A probability function is f(x) = kx for x = 1, 2, 3. This is the value of k.
What is 1/6?
A basketball player makes 70% of free throws. Assuming independent attempts, P(exactly 4 makes in 6 attempts) is approximately this.
What is 0.3241
X ~ N(70, 25). This is the z-score probability to X> 62.
What is 0.9452?
To approximate P(15 ≤ X ≤ 25), these are the corrected normal boundaries.
What are 14.5 and 25.5?
A fair die is rolled twice. The probability that the sum of the two results is 8 is this.
What is 5/36?
If X and Y are independent with Var(X) = 4 and Var(Y) = 9, this is Var(2X − 3Y).
What is 89?
A probability function f(x) = kx², x = 1,2,3, is proposed. This is the value of k, and therefore the probability of X = 3.
What are k = 1/14 and P(X=3) = 9/14?
X ~ Bin(n,p) has mean 15 and variance 10. This is the value of p.
What is p = 1/3?
X ~ N(100, 144). This is the probability that X lies between 88 and 124.
What is approximately 0.8186?
X ~ Bin(40, 0.5). Using a normal approximation with continuity correction, this is the probability that 15 ≤ X ≤ 25.
What is approximately 0.886?