GATE CSE
First time here? Checkout the FAQ!
x
+1 vote
223 views

 

Q) Let $x$ be normal variable with mean $8$ and standard deviation $4$ then $p(X\leq5)$ is 

A). Greater than zero but less than $0.5$

B). Greater than $0.75$

C). Greater than $0.5$ but less than $1$

D). Equal to $0.5$

asked in Probability by Active (1.9k points)   | 223 views
A is correct.

2 Answers

+3 votes

I think the right option is A.

This is the normal distribution curve for this mean and standard deviation μ=8 and σ=4

Since the area under the curve from μ-3σ(-4 here) to μ(8) is 0.5 hence P(x≤5) will be even smaller but will not be zero. Hence option A is correct.

answered by (453 points)  
0 votes
P(x<=5)= (5-8)/4= -3/4= -0.75

probability cant be negative= B is ans
answered by Veteran (44.5k points)  
Top Users Feb 2017
  1. Arjun

    5396 Points

  2. Bikram

    4230 Points

  3. Habibkhan

    3952 Points

  4. Aboveallplayer

    3086 Points

  5. Debashish Deka

    2564 Points

  6. sriv_shubham

    2318 Points

  7. Smriti012

    2240 Points

  8. Arnabi

    2008 Points

  9. mcjoshi

    1696 Points

  10. sh!va

    1684 Points

Monthly Topper: Rs. 500 gift card

20,863 questions
26,023 answers
59,698 comments
22,136 users