Variance Distribution/formual for calculator

[stacey]

Give the variance of the following distribution:

X P(X)
0 0.20
1 0.35
2 0.10
3 0.25
4 0.10

Is there a way to plug this into my calculator and find the answer?

Second question?
How do you figure out a probability value needed to complete the following probabilty distribution?

X P(X)
-5 0.12
-1 0.19
0 0.14
1
4 0.26

 

[galactus]

Do you have Excel?. It will. Just find VAR under the functions list

 

[stacey]

Just need to understand the second question

I figured out how to enter the data into the calculator :idea: :idea:

I am having a time figuring out the missing value in probability distribution. It has to be easy as this variance one was sweet to get the answer rather than going through the formula long hand

 

[galactus]

Remember, the probabilities will sum to 1. Add what you have up and subtract from 1. That's the missing value.

 

[stacey]

So what you are saying: the probabilities will sum to 1. Add what you have up and subtract from 1. That's the missing value.

x P(x)

-2 .09

-1 .18

0 the value would be .33

1 0.15

2 0.25 total was .67 1-.67 the answer is .33 You are the best thank you!