Skip to main content

QUAN 2010 Quiz Examples and Exam Information: Fall 2025

Lauren M. Nelsen

Section Quiz 3 Example Problems

Below are example problems for Quiz 3.
  • Objective 3a Example Problem:

    Example 1.1. Objective 3a Example Problem.

    (This problem will be multiple choice for each part -- you’ll need to choose which of several fractions is the correct probability.)
    A retail industry defines an on-time delivery as one that arrives within 15 minutes of its scheduled time. The following table shows the number of on-time and late deliveries made by three companies during a recent time period:
    Company On-Time Deliveries Late Deliveries
    Company A 80 240
    Company B 125 73
    Company C 150 32
    1. What is the probability that a randomly selected delivery was from Company C and was on-time?
    2. What is the probability that a randomly selected delivery was from Company C or was on-time?
    3. Given that the delivery was on-time, what is the probability it was from Company C?
    4. Given that the delivery was from Company C, what is the probability that it was late?
  • Objective 3b Example Problem:

    Example 1.2. Objective 3b Example Problem.

    (For this problem, round each answer to 4 decimal places. Do not round until you have the final answer.)
    Consider store that sells primarily PCs. Each customer that comes in may buy one, none or several PCs. Let \(X\) denote the number of PCs a customer who comes into the store purchases. Consider the following probability distribution table for \(X\text{:}\)
    \(X_i\) \(0\) \(1\) \(2\) \(3\)
    \(P(X=X_i)\) ??? \(0.374\) \(0.09\) \(0.02\)
    1. What is the value of the missing entry?
    2. Find the expected value of \(X\text{,}\) \(E(X)\text{.}\)
    3. Find the variance of \(X\text{,}\) \(Var(X)\text{.}\)
    4. Find the standard deviation of \(X\text{,}\) \(\sigma_X\text{.}\)

Subsection Solutions

PrevTopNext