Normal Binomial

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Normal Binomial
Message posted by Lettie (via 165.125.17.2) on February 25, 2002 at 3:44 PM (ET)

Problem: I don't understand how to get the probability when it concerns between 2 numbers, am I supposed to add or subtract Z factors. Info: The Small Business Admin estimates 20% new small businesses will dissolve or go bankrupt w/in 2 yrs. Mean=50. What is the probability that between 7 and 9 business will go bankrupt? Between 7 and 15?

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Re: Normal Binomial
Message posted by Phil (via 66.32.157.108) on February 25, 2002 at 11:28 PM (ET)

You are referring to the "Normal Approximation to the Binomial". Try this link.

Look at an example in your book. They add or subtract 1/2 to the values of x to get a more accurate approximation. This is called the "continuity correction."

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