How To Read Z Score Table
How to use the z table.
How to read z score table. First we find the first two digits on the left side of the z table. The value in the table is 8413 which is the probability. For george s example we need to use the 2nd table as his test result corresponds to a positive z score of 0 67. There are two methods to read the z table. On some z tables you will find that the area corresponding to 1 09 z score is 0 3621.
In other words p z 1 53 0 0630. For example consider a data set with a mean of 50 and a standard deviation of 2. If a z score calculation yields a negative standardized score refer to the 1st table when positive used the 2nd table. First use the z table to find the value where the row for 1 0 intersects with 0 00 which is 0 1587. Z x μ σ 50 50 2 0 2 0.
Z score 800 700 180. A z score of zero means that the data value equals the mean. Z score x µ σ. The corresponding area is 0 8621 which translates into 86 21. Then find the value where the row for 1 0 intersects with the column for 0 00 which is 0 8413.
Go to the row that represents the ones digit and the first digit after the decimal point the tenths digit of your z value. Here you want the probability that z is between 1 0 and 1 0. Z score 0 56. Finding a corresponding probability is fairly easy. Roughly 84 13 of people scored worse than him on the sat.
To use the z score table start on the left side of the table go down to 1 0 and now at the top of the table go to 0 00 this corresponds to the value of 1 0 00 1 00. Use z table to see the area under the value x in the z table top row and the first column corresponds to the z values and all the numbers in the middle corresponds to the areas. For example a z score of 1 53 has an area of 0 0630 to the left of it. If a data value also is 50 then the z score is. In this case it is 1 0.