Definition: - z score table is also known as standard normal distribution table. z score table list the area under the standard normal curve between z=0 and the values from .00 to 3.09.
First column gives the value of the first digit after the decimal and top row gives the value of two decimal places of the z score.
Example: - Find the area under the standard normal curve between
1) z=0 and z=1.95
2) z=0 and 3.01
Solution: - 1) We divide the number 1.95 into two portions: 1.9 (the digit before the decimal and one digit after the decimal) and .05 (the second digit after the decimal. (Note that 1.95= 1.9 +0.05).
To find the required area under the standard normal curve, we locate 1.9 in the column for z on the left side of the z score table and .05 in the row for z at the top of the table. The entry where row for 1.9 and column for .05 intersect gives the area under standard normal curve between z=0 and z=1.95.
So the area between z=0 and 1.95 is 0.4744. (From the z score table).
2) Similarly we will get the area between z=0 and 3.01 is 0.4987