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}.
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n(E) | = | 9 | . |
n(S) | 20 |
Discussion:
107 comments Page 4 of 11.
Naina said:
8 years ago
A coin is tossed live times. What is the probability that there is at the least one tail?
Can anyone help me with this question?
Can anyone help me with this question?
Shashi said:
8 years ago
Since the number of events are 20.
So possible events are {3,6,9,12,15,18,5,10,20}.
So answer is 9/20.
So possible events are {3,6,9,12,15,18,5,10,20}.
So answer is 9/20.
Nithya Arun said:
8 years ago
How can we calculate the same problem with big numbers? i.e if tickets numbered 1-200.
Vikram reddy said:
8 years ago
No, here 15 is repeated in 3&5 so the answer is 2/5.
Isha said:
8 years ago
Please help me to solve this-
A number is selected at random from first 50 number. Find the probability that it is a multiple of 3 and 4.
A number is selected at random from first 50 number. Find the probability that it is a multiple of 3 and 4.
Arjun patidar said:
8 years ago
Ans is 9/20 because,
P(A) + P(B) - P(A andB) = P(A OR B )
For p (a) outcome are divide to 20 for getting multiple of 3 we get in rational left after point so 6.
Then also of 5 we get 4 numbers can multiple of five.
After it puts in probability case such as 6/20 + 4/20 - 1/20.
1/20 comes to get no. of both that is only one number 15 and also use short cut as take the LCM of 3&5 we get 15, divide 20 by it to get some thing 1. Left fraction we get 1/ 20 or 1 out of 20 put all in formula.
6/20 + 4/20 - 1/20 = 9/20 answer.
P(A) + P(B) - P(A andB) = P(A OR B )
For p (a) outcome are divide to 20 for getting multiple of 3 we get in rational left after point so 6.
Then also of 5 we get 4 numbers can multiple of five.
After it puts in probability case such as 6/20 + 4/20 - 1/20.
1/20 comes to get no. of both that is only one number 15 and also use short cut as take the LCM of 3&5 we get 15, divide 20 by it to get some thing 1. Left fraction we get 1/ 20 or 1 out of 20 put all in formula.
6/20 + 4/20 - 1/20 = 9/20 answer.
Ravi said:
8 years ago
According to me, From 1 to 20, numbers its 1, 2, 3, 4....., 19, 20 then number which is a multiple of 3 or 5.
Lets take 3 (3, 6, 9, 12, 15, 18 and 5 = (5, 10, 15, 20).
So in 3 we have 6 and 5 we have 4 so it's 6/20 and 4/20 and 1/20.
Solution = 6 + 4 - 1/20 == 9/20 answer.
Lets take 3 (3, 6, 9, 12, 15, 18 and 5 = (5, 10, 15, 20).
So in 3 we have 6 and 5 we have 4 so it's 6/20 and 4/20 and 1/20.
Solution = 6 + 4 - 1/20 == 9/20 answer.
Ravi said:
8 years ago
According to me, From 1 to 20, numbers its 1, 2, 3, 4....., 19, 20 then number which is a multiple of 3 or 5.
Lets take 3 (3, 6, 9, 12, 15, 18 and 5 = (5, 10, 15, 20).
So in 3 we have 6 and 5 we have 4 so it's 6/20 and 4/20 and 1/20.
Solution = 6 + 4 - 1/20 == 9/20 answer.
Lets take 3 (3, 6, 9, 12, 15, 18 and 5 = (5, 10, 15, 20).
So in 3 we have 6 and 5 we have 4 so it's 6/20 and 4/20 and 1/20.
Solution = 6 + 4 - 1/20 == 9/20 answer.
Ujjwal shukla said:
8 years ago
Find the probability that a number from 1 to 300 is divisible by 3 or 7.
Can anyone answer this question.
Can anyone answer this question.
Kavana said:
8 years ago
From 1 to 340, the probability of getting multiples of 8 and 5 is? Please answer this question.
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