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What are the odds?

Probability, Odds and Risk Assessment

Talking about the chances of a freak accident occurring involves probability, odds and something called risk assessment.

When we're talking about probability, we're talking about the number of favorable outcomes divided by the number of possible outcomes. When you flip a coin, there are two possible outcomes, heads or tails, and just one favorable outcome, the side you chose. That means the probability of getting heads (or tails) in a coin toss is 1 in 2. Odds are a little different: The odds of something happening are calculated by dividing the number of favorable outcomes by the number of unfavorable outcomes. A coin toss has two possible outcomes -- it could land on heads or it could land on tails, making the odds of the coin toss 1 to 1. If it sounds confusing, consider that you actually use a non-mathematical version of these skills every day, maybe most often to assess such things as whether the weather forecast is correct. What's the risk? First, we assess the likelihood of something happening. (Does a 50 percent chance of rain mean it will or it won't rain today?) Then we assess the consequences if it were to happen. (I'll bring an umbrella, just in case.)

The National Safety Council, a non-profit organization aiming to reduce the number of accidental yet preventable injuries and deaths in our communities, also uses these calculations to figure out the likelihood of various events and circumstances causing injury or death to the American public. They, among other groups, assess the odds of death per cause or event for two spans of time -- the odds of it happening in a single year and the odds in a lifetime. Let's learn about how they do this as we calculate the odds of being injured at an amusement park.