Final answer:
There are 3^10 = 59049 possibilities if you own 10 stocks.
Step-by-step explanation:
When considering each stock as an independent event, there are three possibilities for each stock: it can go up, go down, or stay unchanged. Since there are 10 stocks, the total number of possibilities is the product of the possibilities for each stock. Using the multiplication rule of counting, we can calculate this as 310 = 59049 possibilities.
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