Question

Suppose a normal distribution has a mean of 98 and a standard deviation of 6. What is P(x<= 104) ?

Answer 1

if the raw score is x = 104, then what is the z-score?

Answer 2

ok then it would be 104-98=6/6=1

Answer 3

That means P(X <= 104) is the same as P(Z <= 1)

Answer 4

you would then use a table like this one

http://www.stat.ufl.edu/~athienit/Tables/Ztable.pdf

to find the area under the curve to the left of z = +1.00

Answer 5

Tell me what you get.

Answer 6

.8413

Answer 7

very good, so because

\[\Large P(Z \le 1) = 0.8413\]

this means

\[\Large P(X \le 104) = 0.8413\]

Answer 8

well both approximate, but you get the idea

Answer 9

ok thanks so much!!

Answer 10

you're welcome