In math, probability is how likely it is that something will occur (or not). Probability is expressed from a range from 0 to 1. A probability of zero means that a thing will definitely not happen – it’s impossible. But a probability of one means that it definitely will happen – it’s certain. Any number larger than 0, but smaller than 1 means that a thing might happen. The number 1/2, or one half, is right in the middle and it means there is a 50/50 chance. Do you think there’s a greater chance for a person to get struck by lightning, or to be hit by a meteorite?
Download Student Worksheet & Exercises
Some key words that help with probability questions are OR and AND. When you see the word OR, it means you should be adding the possible outcomes to find out the probability whether one thing OR another will happen. The word AND means you will probably be multiplying to find the solution. Based on these rules and the information that I share in the video, what are your chances of being struck by lightning AND having a heart attack?
Exercises
- What is the probability of a coin showing tails when flipped?
- What is the probability of a coin showing heads twice in a row?
- What is the probability that heads or tails will show up in a toss?
- What is the probability that heads and tails will show up in two successive tosses?
- A die is rolled once: what is the probability that a four will show up?
- A die is rolled once: what is the probability that a three will show up?
- A die is rolled once: what is the probability that a four or a six will show up?
- A die is rolled twice: what is the probability that a four will show up in all the rolls?
- A die is rolled twice: what is the probability that a four and a two will show up?
- A die is rolled twice: what is the probability that the same number will show up in all the rolls?