Page 209 - Engineering Mathematics Workbook_Final
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Probability & Statistics

            286.  A  probability  distribution  with  right              (a) 0                 (b) 0.5
                   skew is shown in the figure.
                                                                         (c) 1                 (d) 10


                                                                                            [GATE-2008 (IN)]

                                                                  289.  The  cumulative  distribution  function
                                                                         of  a  random  variable  x  is  the
                                                                         probability that X takes the value


                                                                         (a) less than or equal to x
                   The  correct  statement  for  the
                   probability is distribution is                        (b) equal to x

                   (a) Mean is equal to mode                             (c) greater than x


                   (b)  Mean  is  greater  than  median  but             (d) zero                [ESE 2017 (EC)]
                   less than mode                                 290.  The  probability  density  function

                   (c) Mean is greater than median and                   F  ( ) x =  ae − b x    where  x  is  a  random
                   mode                                                  variable whose allowable value range


                   (d) Mode is greater than median                       is from  x = − to  x = +. The CDF
                                                                         for this function for  x   0 is
                   [GATE  2018  (CE-AFTERNOON
                                                                                            a
                                                                             a
                   SESSION)]                                             (a)  e        (b)  (2 e    − bx )
                                                                                                 −
                                                                                bx
                                                                             b              b
                                  ,
            287.  Let      X 1 , X X      and    X      be
                                                   4
                                     3
                                 2
                                                                                             a
                   independent normal random variables                   (c) −  a e    (d)  ( 2 e     − bx )
                                                                                  bx
                                                                                           −
                                                                                                  +
                   with  zero  mean  and  unit  variance.                      b             b
                   The  probability  that  X   is  the                                        [ESE 2017 (EC)]
                                                4
                   smallest among the four is _______.

                                      [GATE-2018 (EC)]
               CUMMULATIVE DISTRIBUTION
                                FUNCTION

            288.  Consider  a  Gaussian  distributed
                   random variable with zero mean and
                   standard  deviation   .  The  value  of
                   its cumulative distribution function at
                   the origin will be






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