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In an Examination, a Student Has to Answer 4 Questions Out of 5 Questions; Questions 1 and 2 Are However Compulsory. Determine the Number of Ways in Which the Student Can Make the Choice.

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प्रश्न

In an examination, a student has to answer 4 questions out of 5 questions; questions 1 and 2 are however compulsory. Determine the number of ways in which the student can make the choice.

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उत्तर

A student has to answer 4 question out of 5 questions.
Since questions 1 and 2 are compulsory, he/she will have to answer 2 question from the remaining 3.
∴ Required number of ways =\[{}^3 C_2 = 3\]

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अध्याय 17: Combinations - Exercise 17.2 [पृष्ठ १६]

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आर.डी. शर्मा Mathematics [English] Class 11
अध्याय 17 Combinations
Exercise 17.2 | Q 12 | पृष्ठ १६

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