The graph depicts the standard normal distribution with mean 0 and standard deviation1. Find the area of the shaded region, find the area below z=0.87

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embizze | High School Teacher | (Level 1) Educator Emeritus

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The area under the standard normal curve for a given `z` value can be found by consulting the `z-` table or using technology. The number in the table represents the area under the curve to the left of the given `z` value.

Thus if `z=.87` , the area under the standard normal curve to the left of `z=.87` is approximately .8078. If the picture you are looking at has the area to the right of `z=.87` , then the area is 1-(the area to the left), or in this case approximately 1-.8078=.1922.

Consulting a graphing calculator (TI-83), I used distr -- normalcdf(-e99,.87) to get .8078498426.

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