Question

Suppose that 20% of dogs will associate a flash of light with a delayed treat given after the flash. 30 dogs are tested in the lab to see if they will learn this association.

Answer 1

Let X denote the number of dogs (out of these 30) that learn the
association.

Answer 2

Compute the expected value and standard deviation of X

Answer 3

Expected=6, but what is SD?

Answer 4

How would you take SD?

Answer 5

The result follows a binomial distribution with n = 30 and p = 0.2.
The standard deviation is given by:
\[\large S.D.=\sqrt{np(1-p)}\]