QBA Quiz 3 - Discrete, Binomial,
Normal Question and answers
correctly solved 2025/2026
Probability Distributions - correct answer ✔A listing of all the outcomes of a random variable and the
probability associated with each outcome
To be a valid probability distribution (2 conditions) - correct answer ✔1. 0 ≤ P(Xi) ≤ 1 for each Xi
2. Σ P(Xi) = 1
For a discrete random variable, population mean equation: - correct answer ✔mu = E(x) = Σx × p(x)
Population mean is also known as the - correct answer ✔expected value of x, long run average
Population variance (not shortcut) - correct answer ✔σ² = v(x) = Σ(Xi-mu)²p(x)
Population variance (shortcut) - correct answer ✔Σx²p(x) - mu²
Binomial Probability Distribution is a - correct answer ✔widely used probability distribution
A binomial experiment (4 things) - correct answer ✔1. sample size
2. 2 outcomes
3. rate of success
4. independent trials, outcome of one trial doesn't affect the outcome of another
The Binomial random variable (x) - correct answer ✔the number of successes in n trials
Normal Question and answers
correctly solved 2025/2026
Probability Distributions - correct answer ✔A listing of all the outcomes of a random variable and the
probability associated with each outcome
To be a valid probability distribution (2 conditions) - correct answer ✔1. 0 ≤ P(Xi) ≤ 1 for each Xi
2. Σ P(Xi) = 1
For a discrete random variable, population mean equation: - correct answer ✔mu = E(x) = Σx × p(x)
Population mean is also known as the - correct answer ✔expected value of x, long run average
Population variance (not shortcut) - correct answer ✔σ² = v(x) = Σ(Xi-mu)²p(x)
Population variance (shortcut) - correct answer ✔Σx²p(x) - mu²
Binomial Probability Distribution is a - correct answer ✔widely used probability distribution
A binomial experiment (4 things) - correct answer ✔1. sample size
2. 2 outcomes
3. rate of success
4. independent trials, outcome of one trial doesn't affect the outcome of another
The Binomial random variable (x) - correct answer ✔the number of successes in n trials
