A class consists of 80 students, 25 of them are girls and 55 are boys. If 10 of them are rich and the remaining are poor and also 20 of them are intel

Monjur Alahi

A class consists of 80 students, 25 of them are girls and 55 are boys. If 10 of them are rich and the remaining are poor and also 20 of them are intelligent, then the probability of selecting an intelligent rich girls is `5//128` b. `25//128` c. `5//512` d. none of these
A. `5//128`
B. `25//128`
C. `5//512`
D. None of these


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Salim Ahmed Kawsar

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Correct Answer - C
Total number of the students is 80. Total number of boys is 55. Therefore are 10 rich, 70 por, 20 intelligent students in the class. Therefore, required probability is
`underset((I))(1/4)xxunderset((R))(1/8)xxunderset((G))(25/80)=5/512`

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