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प्रश्न
Ten students are to be selected for a project from a class of 30 students. There are 4 students who want to be together either in the project or not in the project. Find the number of possible selections.
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उत्तर
| Case I | Case II |
| 4 Students are in | 4 Students are out |
| Number of ways = 26C6 | Number of ways = 26C10 |
Required number = 26C6 + 26C10
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