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Suppose A(1),A(2),…,A(30) are 30 sets ea...

Suppose `A_(1),A_(2),…,A_(30)` are 30 sets each with 5 elements and `B_(1),B_(2),…,B_(n)` are n sets each with 3 elements. Let `underset(i=1)overset(30)uu A_(i)=underset(j=1)overset(n)uu B_(j)` Assume that each element of S belongs to exactly ten `A_(i)`' s and to exactly nine of the `B_(j)`'s then n =

A

15

B

45

C

50

D

cannot be determined

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B
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AAKASH SERIES-SETS AND RELATIONS -PRACTICE EXERCISE
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  2. Number of subsets of the set A={1,2,3,4} is…………..

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  3. The smallest A such that A cup {1,2} = {1,2,3,5,9} is

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  4. If n(A)=10,n(B)=6 and n( C )=5 for three disjoint sets A, B, C then n(...

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  5. If A={1,2,3,4,5},B ={p,q,r,s} then n(A xxB ) =

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  6. If A={0,1},B={1,2},C={2,3} then (A xx B)nn(A xx C)=

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  7. If aN = {ax : x in N} " then " 3N cap 7N =

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  9. If X = {4^(n) - 3n - 1: n in N} " and " Y = {9(n-1): n in N}, where N ...

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  10. Let A={(x,y)//y=e^(x),x in R},B={(x,y)//y=e^(-x),x in R}, then

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  11. The set A={x:x in R,x^(2)=16," and "2x=6} equals

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  12. Let A and B be two sets such that A xx B has 6 elements. If three elem...

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  13. In a class of 70 students takes either Sanskrit or Hindi. 40 take Sans...

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  14. In a city, three daily newspapers A, B, C are published. 42% of the pe...

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  15. Each student in a class of 40, studies at least one of the subjects En...

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  16. An investigator interviewed 100 students to determine their preference...

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  17. A={a, b, c},B={1,2} then the number of relations from A to B is

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  18. A group of 123 workers went to a canteen for cool drinks, ice - cream ...

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