A committee of 10 is to be formed from 8 teachers and 12 students of whom 4 are girls. In how many ways this can be done so that com the committee contains atleast four of either groups (teachers and students) and atleast 2 girls and atleast 2 boys are in the committee.
1 Answers
Two thirds of eth students in a class are boys and the rest girls. It is known that eh probability of a girl getting a first class is 0.25 and that of
Correct Answer - `0.27` We have `P(G)=1//3and P(B)=2//3` ` P(A//G)=0.25and P(A//B)=0.28` Here, A is the event that student chosen will get a first class. So, using total probability theorem, `P(A)=P(B)P(A//B)+P(G)P(A//G)` `2/3xx0.28+1/3xx0.25=0.27`
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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
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...
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Five oys and three girls are sitting in a row of `8` seats. Number of ways in which they can be seated so that not all the girls sit side by side is
Correct Answer - A `(a)` Total no. of arrangement if all the girls do not seat side by side `=["all arrangement"-"girls seat side by side"]` `=8!-(6!xx3!)` `=6!(56-6)=6!xx50` `=720xx50=36000`
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The number of ways in which six boys and six girls can be seated at a round table so that no two girls sit together and two particular girls do not si
Correct Answer - C `(c )` The boys can be seated in `5!` ways. If the girls `g_(1)` and `g_(2)` do not want to sit by the side of `A_(1)` (say)....
2 Answers 1 views
A class has tree teachers, Mr. `X`, Ms.`Y` and Mrs.`Z` and six students `A`, B`, `C`, `D`, `E`, `F`. Number of ways in which they can be seated in a l
Correct Answer - A `(a)` The possible arrangements of teachers and students can be as follows : `(i) T S S T S S T S S` `(ii) S T S...
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5 boys & 4 girls sit in a straight line. Find the number of ways in which they can be seated if 2 girls aretogether & the other 2 are also together bu
Correct Answer - 43200
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In a group of 25 students, 13 can speak English, 12 can speak Hindi and 6 speak neither. How many can speak (i) Both English and Hindi ? (ii) Only Hin
Correct Answer - (i) 6 , (ii) 6 , (iii) 13
2 Answers 2 views
`45%` of the student of a class participated in Physics Olympiad Math Olympiad. 4 students participated in both. Find how many students. (i) Are there
Correct Answer - (i) 40 , (ii) 18 , (iii) 36
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‘Service’ refers A) Nature of work done B) Amount of work done C) Cost of work done D) No livelihood earned
A) Nature of work done
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In how many ways can 11 members of a committee sit at a round table so that the secretary and the joint secretary are always the neighbours of he pres
Correct Answer - 80640
2 Answers 1 views