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Given the Probability that a Can Solve a Problem is 2/3 and the Probability that B Can Solve the Same Problem is 3/5. Find the Probability that None of the Two Will Be Able to Solve the Problem. - Mathematics

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प्रश्न

Given the probability that A can solve a problem is 2/3 and the probability that B can solve the same problem is 3/5. Find the probability that none of the two will be able to solve the problem.

 

उत्तर

\[P\left( \text{ A solving the problem }  \right) = P\left( A \right) = \frac{2}{3}\]
\[P\left( B \text{ solving the problem  } \right) = P\left( B \right) = \frac{3}{5}\]
\[\text{ We need to find out if P } \left( \bar{A} \cap \bar{B} \right) = P\left( \bar{A} \right) P\left( \bar{B} \right) \left[ \text{ A and B are independent events } \right]\]
\[ = \left[ 1 - P\left( A \right) \right]\left[ 1 - P\left( B \right) \right]\]
\[ = \left( 1 - \frac{2}{3} \right)\left( 1 - \frac{3}{5} \right)\]
\[ = \frac{1}{3} \times \frac{2}{5}\]
\[ = \frac{2}{15}\]

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Probability Examples and Solutions
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पाठ 31: Probability - Exercise 31.4 [पृष्ठ ५४]

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आरडी शर्मा Mathematics [English] Class 12
पाठ 31 Probability
Exercise 31.4 | Q 12 | पृष्ठ ५४

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