Module 10 Lesson 1 - Inquire & Watch

 

Inquire: A 20% Chance of Rain

Overview

The weatherman said it might rain today. There’s a $20\%$ chance. That means there’s an $80\%$ chance it won’t. The probability is that it won’t rain. Probability tells us how often an event is likely to occur. It is frequently given as a percentage, but sometimes as a ratio. For example, the odds are 1 to 5 that it will rain today.

We all talk about odds and make predictions, but usually our predictions are based only on our experiences and feelings. This is called subjective probability. However, when a weatherman predicts rain, he isn’t basing his forecast on his feelings. He has computers analyzing complex weather patterns to determine the probability of rain. Probability is based on the number of desired or favorable outcomes divided by the number of possible outcomes. If you know those two numbers, you can figure probability with confidence, and you will probably be right!

Big Question

Watch: Probability is Everywhere

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Module 10 Lesson 1 of 5