Page 193 - Engineering Mathematics Workbook_Final
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Probability & Statistics

                   (d) E, F and G are independent                                1
                                                                         (a) c =
                                         [JAM MS 2018]                           8

                                             
            180.  Let S be the set of all  3 3 matrices                  (b) c = 8
                   having  3  entries  equal  to  1  and  6              (c) X and Y are independent
                   entries  equal  to  0.  A  matrix  M  is
                   picked uniformly at random from the                   (d) P (X = Y) = 0     [NET       JUNE
                   set S. Then                                           2017]

                                                                                   :
                                                  1               183.  Let  X i       1   be  a  sequence  of
                                                                                  i
                   (a) P { M is nonsingular } =
                                                 14                      independent  random  variables  each
                                                                         having  a  normal  distribution  with
                                              1
                   (b) P { M has rank 1 } =                              mean  2  and  variance  5.  Then  which
                                             14                          of the following are true


                                              1                              1  n
                   (c) P { M is identity } =                             (a)     X   converges  in  probability
                                             14                                 i n  1 =  i

                                              1                          to 2.
                   (d) P { trace (M) = 0 } =
                                             14                              1  n
                                                                                    2
                                                                         (b)     X  converges in probability
                                                                                    i
            181.  Suppose  A,  B,  C  are  events  in  a                        i n  1 =
                   common probability space with P(A)                    to 9.

                   =  0.2,  P(B)  =  0.2,  P(C)  =  0.3,                                   2
                                              
                         
                   P ( A B =  ) 0.1,     P ( A C =  ) 0.1,               (c)        1  i n  n  X i            converges   in
                         
                   P (B C =  ) 0.1.  Which  of  the                                 1 =  
                                                                         probability to 4.
                   following  are  possible  values  of
                   P ( A B C    )?                                             n     X i     2
                                                                         (d)                  converges   in
                                                                                 i= 1   n  
                   (a) 0.5                      (b) 0.3
                                                                         probability to 0.
                   (c) 0.4                      (d) 0.9
                                                                                              [NET DEC 2016]

            182.  Let  c R  be a constant. Let X, Y be           184.  A  and  B  are  two  events  defined  as
                   random      variables     with     joint              follows:
                   probability density function
                                                                         A: It rains today with P(A) = 40%
                               cxy    for  0 x      1
                                             
                                                    y
                              
                           )
                    f  ( ,x y =                         .
                                0        otherwise                      B: It rains tomorrow with P(B) = 50%
                              
                   Which  of  the  following  statements                 Also, P(it rains today and tomorrow)
                   are correct?                                          = 30%


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