Question

Turn 13 into a z-score: (13-7.8)/4.98 = 1.04

Turn 8 into a z-score: (8-7.8)/4.98 = .04

how do I find each on the z score table?

Answer 1

For 13 we get Z score as 1.04

for 1.04 we split it in to 1.0 +0.04

So for finding the value corresponding to 1.04 on Z table, follow the steps.

1. In the row headed look for 1.0 value

2. In column headed column look for 0.04 value

3. Now take the combine value of row having header 1.0 and column having header 0.04

So we get - P( z 1.04) =  0.8508

Similarly for finding the area corresponding to Z score= 0.04

for 0.04 we split it in to 0.0 +0.04

1. Look the row headed column 0.0

2. Look the column headed column 0.04

3. The the column value in between

So we get - P(z=0.04) = 0.5160

Hope this will help you. Thank you :)