How to calculate a stock's expected return, variance, and standard deviation using probabilities

I start with a distribution of stock returns (probabilities and outcomes). I then compute the expected return, variance, and standard deviation using an Excel spreadsheet. Note these are population parameters, not estimates.
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[@yescarolinecansing]

so straight forward and helpful thank you

[@sophynasambu118]

Made it easier! Amazing.

[@user-hx2sl6jp3u]

you forgot to take first the mean of the variance and then the sqrt of it.

[@elizabetheuesandray4527]

Really helpful, thank you sir.

[@jd0879]

There's no formulas in excel to get to G6 in one shot?

[@Smiley_fan25]

What about if you only have the expected return but no probabilities? How do you calculate the standard deviation?

[@gerryc4185]

can someone help me with this problem Consider the following information:
State of Economy Probability of State of Economy Rate of Return if State Occurs
Stock A Stock B Stock C
Boom 0.25 0.18 0.37 0.27
Good 0.15 0.13 0.14 0.15
Poor 0.40 −0.01 −0.11 −0.04
Bust 0.20 −0.19 −0.16 −0.13
a. Your portfolio is invested 40 percent each in Stocks A and C and 20 percent in Stock B. What is the expected return of the portfolio? Find the variance and standard deviation. I got the expected return and it is 3.575 but I CANNOT GET the other two. please help

[@tejesaladdin6484]

how to calculate probabilities for the return which is defined in this? Please let me know how it is.

[@valdezmaury467]

How did you "copy it down for each one" I keep having to manually put it into it. Sorry do not know excel