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Hey there! Have you ever wondered what the chances are of rolling a six, or if it's going to rain today? That's what probability is all about!
Probability is the math word for how likely something is to happen. We measure it on a scale from 0 (completely impossible) to 1 (absolutely certain).
Think of flipping a coin. There are only two possible outcomes: Heads or Tails. Since both sides are equally likely, we say the probability of getting Heads is 1 out of 2, or 1/2.
To find a basic probability, we write a fraction. The top number is the number of successful outcomes we want, and the bottom number is the total number of all possible outcomes.
✏️ Worked example
You have a standard six-sided die. What is the probability of rolling an even number (2, 4, or 6)?
- Identify the total number of possible outcomes on a six-sided die. The possible outcomes are 1, 2, 3, 4, 5, and 6. This gives us a total of 6 outcomes.
- Identify the successful outcomes we want. We want an even number, which are 2, 4, and 6. This gives us 3 successful outcomes.
- Write the probability as a fraction: Successful Outcomes / Total Outcomes. This gives us 3/6.
- Simplify the fraction. 3/6 can be simplified to 1/2 by dividing both numbers by 3. So, the probability of rolling an even number is 1/2 (or 50%).
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