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Three Persons Enter a Railway Compartment. If There Are 5 Seats Vacant, in How Many Ways Can They Take These Seats? (A) 60 (B) 20 (C) 15 (D) 125

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प्रश्न

Three persons enter a railway compartment. If there are 5 seats vacant, in how many ways can they take these seats?

विकल्प

  • 60

  • 20

  • 15

  • 125

MCQ
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उत्तर

60
Three persons can take 5 seats in 5C3 ways. Moreover, 3 persons can sit in \[3!\] ways.
∴ Required number of ways =\[{}^5 C_3 \times 3! = 10 \times 6 = 60\]

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अध्याय 17: Combinations - Exercise 17.5 [पृष्ठ २५]

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आर.डी. शर्मा Mathematics [English] Class 11
अध्याय 17 Combinations
Exercise 17.5 | Q 13 | पृष्ठ २५

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