standard deviation of expected returns for HP12c following, expected, standard, returns, problem

scruge

Does anyone know the keystrokes to calculate this problem on HP?

Given the following probability distribution, find the standard deviation of expected returns.

Event P(RA) RA

Recession 0.10 -5%

Below Average 0.30 -2%

Normal 0.50 10%

Boom 0.10 31%

manasib

When calculation expected return and standard deviation with probability like this case, you must use the formula manually. I think it is not so difficult.

Siddimaula

that is what I thought. Thanks.