Z Score Chart

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Z Score Chart
Z Score Chart
Use this chart to find the area under a normal curve when finding
An approximation for a binomial distribution. Negative z-score - value is to the left of the
mean. Positive z-score - value is to the right of the mean.
Negative Z Scores Chart, Normal Distribution Table
The chart shows the values of negative z scores which is either to the left or below the
mean value. The whole number and the first digit after the decimal point of the z score
is displayed in the row and the second digit in the column of the normal distribution
Standard Normal Distribution Table
The table below can be used to find the area under the curve from the central line to
any "Z-score" value up to 3, in steps of 0.01.

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This will then tell you what portion of the population are within "Z" standard
deviations of the mean. Instead of one LONG table, we have put the "0.1"s
running down, then the "0.01"s running along.
For example, to find the area under the curve between 0 and 0.45, start at
the row for 0.4, and read along until 0.45: there is the value 0.1736
Because the curve is symmetrical, the same table can be used for values
going either direction, so a negative 0.45 also has an area of 0.1736
To find the area between two negative z scores is, by symmetry of the bell
curve, equivalent to finding the area between the corresponding positive z
scores. Use the standard normal distribution table to look up the areas that
go with the two corresponding positive z scores. Next subtract the smaller
area from the larger area.
For example, finding the area between z1 = -2.13 and z2 = -.45, is the same
as finding the area between z1* = .45 and z2* = 2.13. From the standard
normal table we know that the area associated with z1* = .45 is .674. The
area associated with z2* = 2.13 is .983. The desired area is the difference of
these two areas from the table: .983 - .674 = .309.

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