Exam SG2: Probability

Front

What is the definition of probability?

Back

Probability is a measure of the likelihood that an event will occur, expressed as a number between 0 and 1.

Front

What is the formula for calculating the probability of an event?

Back

The probability of an event A is given by P(A) = \frac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}}.

Front

How do you calculate the probability of picking a specific color marble from a bag?

Back

Count the number of marbles of that color and divide by the total number of marbles in the bag.

Front

What is the probability of not choosing a specific item?

Back

The probability of not choosing an item is 1 minus the probability of choosing that item.

Front

What is the formula for the probability of the union of two events?

Back

P(A or B) = P(A) + P(B) - P(A and B).

Front

How do you find the probability of an event occurring at least once?

Back

Use the complement rule: P(at least one) = 1 - P(none).

Front

What is a Venn diagram and how is it used in probability?

Back

A Venn diagram visually represents the relationships between different sets, helping to calculate probabilities involving unions and intersections.

Front

If 40% of households own a dog and 32% own a cat, what is the probability that a household owns a dog or a cat?

Back

Use the formula: P(dog or cat) = P(dog) + P(cat) - P(dog and cat).

Front

What does it mean for events to be independent in probability?

Back

Two events are independent if the occurrence of one does not affect the probability of the other.

Front

What is the probability of rolling a sum of 7 with two dice?

Back

There are 6 favorable outcomes for rolling a sum of 7 out of 36 total outcomes, so P(sum of 7) = \frac{6}{36} = \frac{1}{6}.