The standard deviation is actually the square root of np(1-p). In this example p = 0.48 so 1 - p = 1 - 0.48 = 0.42
I hope this helps,
Pat wrote back
Sorry, but that tdid not help.
the problem answer is as follows np=(40)(0.48)=19.2. I understand that multiply this.
than they did a standard deviation of the distribution of the number, a sign that looks like a square root but it is not so under this sign it sys np(1-p)=that same sign (40)(0.48)(1-0.48~3.160 I do not understand how they got 3.160. please help. I am 55 years and in school and this is hurting me. thank you for your help. Also is there somewhere on the internet where I can download the different math symbols?
From what you are describing you see
What this means is calculate
Then te symbol √ says to take the square root so
√9.984 = 3.159746
Does this help?