# Financial Calculator HP 10bII - Standard Deviation with Probability

I have a financial calculator and am trying to use it to calculate the standard deviation when probability is involved.

For a standard deviation question say on the numbers $1$, $5$, $6$, $10$

Press 1, E+
Press 5, E+
Press 6, E+
Press 10, E+
Press Stat Button - ox


Answer $3.2$

However I have just been presented with a question in the format

$$\begin{array}{l|l} \text{Probability}&\text{Score}\\ \hline 0.1&1\\ 0.3&5\\ 0.4&6\\ 0.2&10 \end{array}$$

With the forumla:

$$\text{stdev}^2 = \sum (\text{Probability} \times (\text{Score} - \text{Average Score}))^2$$

How would I do this on my calculator?

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