Question

In a large population of high school students 20% have experienced math anxiety. you take a random sample of 10 students from this population. the standard deviation of the number of students in the sample who have experienced math anxiety is

Answer 1

Given : p = 20% = 0.20 , n = 10

Solution:

The mean is given by: = np

i.e. = (10)(0.20) = 2

Now , the standard deviation can be calculated as :

= (q)

Where , q = 1-p

i.e. q = 1-0.20 = 0.80

So , = (2*0.80) = 1.265

Answer : 1.265

answered by: anonymous