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ECZ Grade 12 School Certificate Probability — practice questions

Explore 34 free Probability questions in ECZ Grade 12 School Certificate Mathematics. Open each question or exercise to read its content, reference answers and available explanation.

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Probability questions and exercises with answers

Showing questions 1–30 of 34.

What is the set of all possible outcomes of an experiment called?Read the answer and worked solution →Mutually exclusive events can never do what?Read the answer and worked solution →A bag holds 3 red balls, 5 blue balls and 2 yellow balls. What is the chance of drawing a yellow ball?Read the answer and worked solution →Two events are independent. What does knowing that one of them happened tell you about the other?Read the answer and worked solution →Two ordinary six-sided dice are rolled. What is the probability that the two numbers add up to 9?Read the answer and worked solution →On a given day the chance of rain is 0.4. When it rains, the chance a match is called off is 0.5. What is the chance of both?Read the answer and worked solution →Match each probability word to its meaningRead the answer and worked solution →Judge each probability claimRead the answer and worked solution →Complete the definition of conditional probabilityRead the answer and worked solution →True or false: conditional probabilityRead the answer and worked solution →Independent or mutually exclusive?Read the answer and worked solution →Match each rule to its nameRead the answer and worked solution →IndependenceRead the answer and worked solution →Order the steps for a Bayes' theorem questionRead the answer and worked solution →Complete the conditions for a partitionRead the answer and worked solution →True or false: independence versus exclusivityRead the answer and worked solution →Assertion and reasonRead the answer and worked solution →Tap every statement that follows from independenceRead the answer and worked solution →The multiplication ruleRead the answer and worked solution →Spot the one that does not belongRead the answer and worked solution →Two are true, one is notRead the answer and worked solution →Three of these are wrong. Find the one that holds.Read the answer and worked solution →Complete the theorem of total probabilityRead the answer and worked solution →Which theorem answers which question?Read the answer and worked solution →True or false: total probability and BayesRead the answer and worked solution →Match each historical figure to their contributionRead the answer and worked solution →The Historical NoteRead the answer and worked solution →Flip and pair: notation with meaningRead the answer and worked solution →Order the reasoning: from a partition to a posteriorRead the answer and worked solution →Tap every quantity that is a probabilityRead the answer and worked solution →

Worked practice questions

What is the set of all possible outcomes of an experiment called?

  1. The sample space
  2. The event set
  3. The trial run
  4. The outcome list
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Correct answer: A. The sample space

1. An experiment is any process whose result is uncertain. 2. The set of all possible outcomes of that experiment is the sample space. 3. Every experiment has exactly one sample space. _Source: Siyavula Mathematics Grade 11 (Everything Maths, CC BY 4.0), Chapter 10: Probability_

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Mutually exclusive events can never do what?

  1. Occur in any order
  2. Occur at the same time
  3. Occur more than once
  4. Occur in a sample space
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Correct answer: B. Occur at the same time

1. Mutually exclusive events have no outcomes in common. 2. So they can never occur at the same time. 3. A number being even and the same number being odd is an example of such a pair. _Source: Siyavula Mathematics Grade 11 (Everything Maths, CC BY 4.0), Chapter 10: Probability_

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A bag holds 3 red balls, 5 blue balls and 2 yellow balls. What is the chance of drawing a yellow ball?

  1. It is 1 in 5
  2. It is 1 in 2
  3. It is 2 in 8
  4. It is 1 in 10
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Correct answer: A. It is 1 in 5

1. Every ball is equally likely to be drawn, so outcomes can simply be counted. 2. Count the sample space first: 3 plus 5 plus 2 gives 10 balls in total. 3. Count the event set next: there are 2 yellow balls. 4. The probability is 2 out of 10, which simplifies to 1 out of 5. 5. Answering 1 in 10 counts only one yellow ball instead of both of them. _Source: Siyavula Mathematics Grade 11 (Everything Maths, CC BY 4.0), Chapter 10: Probability_

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More Mathematics topics

Binomial TheoremCorrelation and RegressionGeometryMeanMedianPermcombPermutations and CombinationsProbability & Statistics