Practice Basic Probability in Statistics

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Quick Recap

The chance or likelihood that an event will occur, expressed as a number between 0 (impossible) and 1 (certain).

Probability is a way of putting a number on chance. Flipping heads? That's 0.5 (half the time). Rolling a 6 on a die? That's \frac{1}{6} (one out of six possible outcomes). It's like asking 'if we did this many times, what fraction would this outcome happen?'

Example 1

easy
A bag contains 3 red, 5 blue, and 2 green marbles. What is the probability of drawing a blue marble?

Example 2

easy
A fair six-sided die is rolled. What is the probability of rolling an even number?

Example 3

easy
A spinner has 8 equal sections numbered 1โ€“8. What is the probability of landing on a number greater than 5?

Example 4

easy
A card numbered 1 through 10 is chosen at random. What is the probability that the number is prime?