Test your understanding of fundamental probability concepts with this easy-level quiz. Designed for beginners, this quiz covers probability rules, terminology, and simple scenarios relevant to basic probability calculation and interpretation.
What is the probability of tossing a fair coin and getting heads?
Explanation: The probability of getting heads with a fair coin is 0.5 because there are two equally likely outcomes: heads or tails. 1.0 would mean a certain event, which is not the case here. 0.2 is too low for a two-outcome situation, and 2.0 is not possible as probabilities cannot exceed 1.
Which value below can never be a probability of an event?
Explanation: Probabilities are always between 0 and 1, inclusive, so -0.1 is impossible. Zero indicates an impossible event, 0.75 is a valid probability, and 1 means a certain event. Negative probabilities do not exist in standard probability theory.
If a bag contains 4 red and 6 blue marbles, what is the probability of randomly drawing a red marble?
Explanation: There are 4 red marbles out of 10 total marbles, so the probability is 4/10 = 0.4. 0.6 represents the chance of picking a blue marble, not red. 0.25 is incorrect because it would require 4 out of 16. 0.5 would only be correct if red and blue were equal in number.
What is the probability of rolling a 7 on a standard six-sided die?
Explanation: A standard die only has faces numbered 1 through 6, so rolling a 7 is impossible, making the probability 0. 1/7 and 1/6 refer to possible outcomes, not impossible ones. The option 7 is not a probability value.
If a box only contains blue balls, what is the probability of randomly selecting a blue ball?
Explanation: When every possible selection is blue, the probability is 1, meaning it's certain to happen. Zero only applies to impossible events, 0.5 would indicate equal probability between two outcomes, and 10 is not a valid probability.
If the chance of rain is 0.3, what is the probability it will not rain?
Explanation: The probability of not raining is 1 minus the probability of rain, so 1 - 0.3 equals 0.7. 0.3 is the probability of rain, not its complement. 0.5 would represent equally likely rain or no rain, and 1.3 is invalid as probabilities cannot exceed 1.
Which pair of events are mutually exclusive when rolling a die: 'rolling an even number' and 'rolling a 3'?
Explanation: Rolling an even number (2, 4, 6) and rolling a 3 cannot happen at the same time, so the events are mutually exclusive. 'No' would only be correct if the events could happen together, which is not the case. 'Sometimes' and 'Never' do not specifically address the scenario.
What is the probability of drawing a heart from a standard deck of 52 playing cards?
Explanation: There are 4 suits in a deck, so 13 hearts out of 52 cards gives a probability of 13/52, which simplifies to 1/4. 1/13 would be correct for a particular card like the ace of hearts. 1/2 and 1/52 do not represent the proportion of hearts in the deck.
In tossing a fair coin, the probability of getting tails is best described as:
Explanation: A fair coin means both heads and tails have a probability of 0.5, making them equally likely. Saying it’s less or more likely is incorrect for a fair coin. 'Impossible' is incorrect, since tails can occur.
When drawing a single card from a deck, what is the probability of getting a king or a heart?
Explanation: There are 13 hearts and 4 kings, but 1 king of hearts is in both categories. So add 13 and 4, then subtract 1 for double-counting, getting 16. 13/52 is only hearts, 4/52 is only kings, and 17/52 does not account for overlap.
If all outcomes are equally likely, what term describes this scenario?
Explanation: Uniform probability means every outcome has the same chance of occurring. Uncertain probability is not a standard term and does not describe equally likely chances. Negative probability is invalid and irregular is not used in this context.
What does P(A) represent in probability, where A is an event?
Explanation: P(A) is the notation for the probability of event A. Possibility and percentage are related but not the mathematical definition. 'Prediction about A' is too vague and not the precise meaning.
A probability of zero corresponds to which type of event?
Explanation: A probability of zero means the event cannot happen, making it impossible. Unlikely events have probabilities greater than zero but less than one. 'Possible' covers any chance above zero, and 'Certain' corresponds to probability one.
How many possible outcomes are there when rolling two standard six-sided dice?
Explanation: Each die has 6 outcomes, so together they make 6 × 6 = 36 possible outcome pairs. 12 and 6 are too low and miss the combination logic, while 18 doubles instead of multiplying the options.
If the probability of an event is 0.25, what is this probability as a percentage?
Explanation: To convert a probability to percentage, multiply by 100. So, 0.25 × 100 = 25%. 2.5% and 0.25% are wrong by a factor of ten or one hundred, and 75% is three times higher than the correct value.
What is the name of the event that consists of all outcomes not in event A?
Explanation: The complement includes all outcomes not in a specified event. 'Component' refers to parts, not the opposite, while 'Supplement' means something added, and 'Completion' does not relate to probability events.