Aptitude - Probability - Discussion
Discussion Forum : Probability - General Questions (Q.No. 1)
1.
Tickets numbered 1 to 20 are mixed up and then a ticket is drawn at random. What is the probability that the ticket drawn has a number which is a multiple of 3 or 5?
Answer: Option
Explanation:
Here, S = {1, 2, 3, 4, ...., 19, 20}.
Let E = event of getting a multiple of 3 or 5 = {3, 6 , 9, 12, 15, 18, 5, 10, 20}.
![]() |
n(E) | = | 9 | . |
n(S) | 20 |
Discussion:
107 comments Page 2 of 11.
Dharmesh Patel said:
1 decade ago
Yes answer is Only and only 9/20.
Sugnya said:
1 decade ago
The answer is 1/2 because if there is same number we should include it. This not union or intersection model.
Albert said:
1 decade ago
Final answer is 9/20
Kiruba said:
1 decade ago
Thanks sneha. Ans is 9/20.
Rach said:
1 decade ago
Circular board of i feet has area Pi. The area of the region containing all points which are closed to center than to periphery will be Pi/4. Hence the proportion to hit near the center is 1/4=.25. So D is the correct answer.
Rahul said:
1 decade ago
@rach.
Hai rach I didn't get you. Can you please explain clearly.
Hai rach I didn't get you. Can you please explain clearly.
Sreejith said:
1 decade ago
Hello Rach,
How did you get that as pi/4?
Or anybody else knows?
How did you get that as pi/4?
Or anybody else knows?
Pinki said:
1 decade ago
How we calculate n(E) and n(S). ?
Geeta chauhan said:
1 decade ago
I cant understand the ans please explain me.
Rammu said:
1 decade ago
n(E) = number of possible events
n(S) = total number of samples
Eg. Tickets which is numbered 1 to 20 is n(S)
The possible tickets drawn which has number multiple of 3 and 5 is n(E).
n(S) = total number of samples
Eg. Tickets which is numbered 1 to 20 is n(S)
The possible tickets drawn which has number multiple of 3 and 5 is n(E).
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers