Combinations with Piano Keys

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How many sound combinations can be created by the $10$ selected piano keys if each sound combination contains from $3$ to $10$ keys?

Can anyone throw at least a hint? I am having difficulties with this question.

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Hint: Each combination can have $3$ to $10$ keys which means for a certain group of selected piano keys to be called a combination, at least $3$ keys must be played. For keys other than these $3$, there are two possibilities, either being played or not. What follows is simply the principle of counting.