Loading [MathJax]/jax/output/HTML-CSS/jax.js

StatTutor Lesson - Continuous Probability Models

true
Stat Tutor
true
true
You have completed 0 question sequences out of 4.
StatTutor: Continuous Probability Models
Video Player is loading.
Current Time 0:00
Duration 0:00
Loaded: 0%
Stream Type LIVE
Remaining Time 0:00
 
1x
    • Chapters
    • descriptions off, selected

      Question 1

      136

      Question 1.

      Consider the variable Joe’s weight next Friday. What is the probability he weighs 170 pounds (the same weight he told you for last Friday)?

      Correct. Variables like height and weight are continuous. People typically round their actual weight (which can be measured in pounds, ounces, and fractions of ounces – whatever the accuracy of your scale is) to the nearest 5 or 10 pounds. Joe’s weight will not be exactly 170 pounds next Friday. The probability of Joe weighing 170 pounds will be 0.
      Incorrect. Variables like height and weight are continuous. People typically round their actual weight (which can be measured in pounds, ounces, and fractions of ounces – whatever the accuracy of your scale is) to the nearest 5 or 10 pounds. Joe’s weight will not be exactly 170 pounds next Friday. The probability of Joe weighing 170 pounds will be 0.
      2
      Try again.

      Questions 2-3

      275

      Question 2.

      Motor Vehicles table image

      The time spent waiting at a traffic light can be considered a random variable with values from 0 seconds (it’s green when you approach and can go on through) to 30 seconds with the distribution shape shown above. What is the height of this distribution? Express your answer in decimal form using three decimal places.

      Correct. The entire area under the distribution curve must be 1. This rectangle has a base of length 30; we have H x 30 = 1; solve for H.
      Incorrect. The entire area under the distribution curve must be 1. This rectangle has a base of length 30; we have H x 30 = 1; solve for H.
      2
      Try again.

      Questions 4-6

      364

      Question 4.

      From the standard Normal table, P(z 1.5) =

      Correct. Using the standard Normal table, locate 1.5 in the left hand margin, then read the entry under the .00 column.
      Incorrect. Using the standard Normal table, locate 1.5 in the left hand margin, then read the entry under the .00 column.
      2
      Try again.

      Question 7

      443

      Question 7.

      Laundry detergent boxes are filled according to an approximately Normal distribution with mean 34.15 ounces and standard deviation 0.1 ounces. What is the probability a randomly selected box has less than the 34 ounces of advertised weight?

      Correct. The standardized value for a 34 ounce weight is z = (34 – 34.15)/0.1 = -1.5. You already found the probability that a standard Normal random variable is less than 1.5 standard deviations below the mean.
      Incorrect. The standardized value for a 34 ounce weight is z = (34 – 34.15)/0.1 = -1.5. You already found the probability that a standard Normal random variable is less than 1.5 standard deviations below the mean.
      2
      Try again.