GED Practice

GED Math Review: Independent and Dependent Probability


Questions:

A. Classify the events in each scenario as independent or dependent.

  1. a) A golf bag contains 5 white tees and 1 blue tee. If John selects 2 tees at random from the bag, what is the probability that they are both white?

    b) A spinner has 4 equal sections colored red, yellow, green, and blue. What is the probability that the spinner will land on red twice in a row?
  2. a) A quarter is flipped twice. What is the probability that it land on heads for the first flip and tails on the second flip?

    b) A company decides to select two workers at random to attend a computer class. Stephanie and Yuki both place their names in a hat, along with eight other workers. What is the probability that Stephanie and Yuki's name are chosen from the hat?

    Refer to the following information to answer questions 3 and 4.

    A game is played by spinning a spinner and then, without looking, drawing a card. After each turn, the card is replaced and the cards are shuffled.

  3. What is the chance that a player will spin red and then draw a 4 or higher?
    • 1/24
    • 1/8
    • 1/6
    • 1/4
  4. Rounded to the nearest percent, what is the chance that a player will spin either red or blue and then draw a 5?
    • 4%
    • 5%
    • 16%
    • 17%
  5. Max rolls standard six-sided number cubes. What is the chance, expressed as a fraction, that both will show a 6?
    • 1/36
    • 1/30
    • 1/6
    • 1/3
  6. Ace Manufacturing builds air conditioning units. On Friday, 20 units were built with defective parts. The company built a total of 100 units on Friday. Before the mistake was discovered, the company shipped two air conditioners. What is the probability (to the nearest percent) that both air conditioners have defective parts?
    • 3%
    • 4%
    • 38%
    • 40%
  7. Alex has 10 cards: 5 hearts and 5 diamonds. Sharon draws and keeps two of Alex's cards. What is the probability that both cards are hearts?
    • 2/10
    • 2/9
    • 1/4
    • 1/2
Answers:

  1. a) dependent b) independent
  2. a) independent b) dependent
  3. 1/4
  4. 17%
  5. 1/36
  6. 4%
  7. 2/9



Reference:




Complete Test Preparation for the GED Test 2014 by Steck-Vaughn