मराठी

5c1 + 5c2 + 5c3 + 5c4 +5c5 is Equal to (A) 30 (B) 31 (C) 32 (D) 33

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प्रश्न

5C1 + 5C2 5C3 + 5C4 +5C5 is equal to

पर्याय

  • 30

  • 31

  • 32

  • 33

MCQ
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उत्तर

 31

\[{}^5 C_1 + {}^5 C_2 + {}^5 C_3 + {}^5 C_4 + {}^5 C_5\]
\[= {}^5 C_1 + {}^5 C_2 + {}^5 C_2 +^5 C_1 + {}^5 C_5\]

\[= 2 \times^5 C_1 + 2 \times {}^5 C_2 +^5 C_5 \]
\[ = 2 \times 5 + 2 \times \frac{5!}{2! 3!} + 1 \]
\[ = 10 + 20 + 1 \]
\[ = 31\]

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पाठ 17: Combinations - Exercise 17.5 [पृष्ठ २५]

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आर.डी. शर्मा Mathematics [English] Class 11
पाठ 17 Combinations
Exercise 17.5 | Q 10 | पृष्ठ २५

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