EMP Q.19

0. A five figure number is formed by the digits 0, 1,2,3,4 without repetition. Then the probability that the number formed is divisible by 4 is

  • Option : B
  • Explanation : The five digits can be arranged in 5! ways, out
    of which 4! will begin with zero.

    Total number of 5-figure numbers formed
                         = 5! - 4! = 96.
    Those numbers formed will be divisible by 4
    which will have two extreme right digits
    divisible by 4,
    i.e., numbers ending in 04, 12,20,24,32,40.
    Now, numbers ending in 04 = 3! = 6,
    numbers ending in 12 = 3! - 2! = 4,
    numbers ending in 20 = 3! = 6,
    numbers ending in 24 = 3! - 2! = 4,
    numbers ending in 32 = 3! - 2! = 4,
    and numbers ending in 40 = 3! = 6.
    [Numbers having 12, 24, 32 in the extreme right
    are (3! - 2!), since the numbers having zero on
    t.he extreme left are to excluded.]
    Total number of favourable ways
    6 + 4 + 6 + 4 + 4 + 6 = 30
    Hence,    required probability = Probability

Cancel reply

Your email address will not be published. Required fields are marked *


Cancel reply

Your email address will not be published. Required fields are marked *