T6.7. Which of the following random variables is geometric?
(a) The number of times I have to roll a die to get two6s.
(b) The number of cards I deal from a well-shuffled deck of52 cards until I get a heart.
(c) The number of digits I read in a randomly selected row of the random digits table until I find a7.
(d) The number of 7sin a row of40 random digits.
(e) The number of 6sI get if I roll a die 10times

Short Answer

Expert verified

The random variables is geometric. So, option (c) is correct.

Step by step solution

01

Concept introduction

To find that the given random variable is geometric or not. Since a variable operates a geometric distribution, if the number of failures before the first success then each draw is independent of the previous ones.

02

Explanation

The random variables are geometrically verified as follows:

  1. Not geometric, because the number of failures comes first, followed by the primary two successes.
  2. It is not geometric because no substitution of cards is made.
  3. Geometric, because it satisfies all of the geometric distribution's conditions.
  4. Not geometric because the number of successes rather than the number of failures prior to rapid success is calculated.
  5. Not geometric because the number of successes rather than the number of failures before the rapid success is counted. As a result, option (c) is right.

The number of digits in a number I randomly select a row from the random digits database and read it till I discover a 7

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