A fair coin is tossed repeatedly until a head is obtained for the first time. Let denote the number of tosses required. The value of the distribution function of at 3 is
Tap an option to check your answer.
1 markStatisticsRandom variables and standard distributionsGeometric and hypergeometric distributionsModerateabout 2 min
DSE 2010 Question 14: Random variables and standard distributions
Answer and worked solution
Checking your account…
Plain-text version
A fair coin is tossed repeatedly until a head is obtained for the first time. Let X denote the number of tosses required. The value of the distribution function of X at 3 is (A) 3/4 (B) 1/2 (C) 7/8 (D) 7/16
Random variables and standard distributions has come up 173 times in 7 exams since 2005.
What this question tests
This question is on Geometric and hypergeometric distributions, part of Random variables and standard distributions in Statistics.
Waiting for a first success, and successes in draws without replacement.
TestStop has 7 past-paper questions on this subtopic.
Similar questions from other papers
- Given below are two statements: Assertion A: A random variable is a numerical description of the outcome of an experiment. Reason R: The particular numerical value of a…
- Suppose, a random variable X follows a Poisson distribution with parameter λ=25. The coefficient of variation of the distribution is (rounded off to two decimal places)
- It is given that Prob(-1≤ z≤ 1)=0.683, Prob(-2≤ z≤ 2)=0.954, and Prob(-3≤ z≤ 3)=0.997, when z follows a standard normal distribution. If X follows a normal distribution…
- Suppose that the random variable X takes on the values: -1, 0, and 2 with probability 1/8, 1/2 and 3/8. Find the expected value of X.
- If X is a continuous random variable whose probability density function is given by f_X(x) = { 1/x² for 1 < x < ∞; 0 elsewhere } Then the median of X is (in integer)
Question from the DSE 2010 paper. Solutions are TestStop's own. Not affiliated with or endorsed by any examination authority.