To arrange a performance program with 6 singing programs and 4 dance programs, where no two dance programs can be adjacent, how many different arrangements are possible? (Only the formula needs to be written, no need to calculate.)
Solution
This problem can be solved using the method of inserting spaces. Since no two dance programs can be adjacent, we can consider the space before and after each of the 6 singing programs as a potential position for inserting a dance program, resulting in 7 spaces. We need to arrange the dance programs into these spaces to ensure they are not adjacent. There are ways to do this. After arranging the dance programs, there are ways to arrange the singing programs.
Therefore, the total number of arrangements is .
The answer is .
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