You are not logged in.
#76 2006-04-24 02:51:57
- krassi_holmz
- Real Member
Offline
Re: *** Problems
27.
IPBLE: Increasing Performance By Lowering Expectations.
#77 2006-04-24 02:55:21
- krassi_holmz
- Real Member
Offline
Re: *** Problems
28.
IPBLE: Increasing Performance By Lowering Expectations.
#78 2006-04-24 14:09:19
- ganesh
- Moderator
Offline
Re: *** Problems
Excellent, krassi_holmz! Keep up the good work!
Character is who you are when no one is looking.
#79 2006-04-25 15:07:06
- ganesh
- Moderator
Offline
Re: *** Problems
***29. Out of 40 students, 25 are boys, 16 are married, 10 are married boys. What is the probability that a chosen student would be an unmarried girl?
Character is who you are when no one is looking.
#80 2006-05-03 01:06:04
- ganesh
- Moderator
Offline
Re: *** Problems
***30. If x,y, and z be respectively the sums of p, q, and r terms of an Arithmetic Progression, prove that
Character is who you are when no one is looking.
#81 2006-06-08 00:26:04
- ganesh
- Moderator
Offline
Re: *** Problems
***31. Two numbers are selected at random from 1,2,3,4,....100 and are multiplied. Find the probability of the product being a multiple of 3.
***32. A and B are two independent events. The probability that both A and B occur is 1/6 and that of neither of them occuring is 1/3. Find the probability of occurence of A.
Character is who you are when no one is looking.
#82 2006-06-12 22:34:34
- Ninja 101
- Power Member
Offline
Re: *** Problems
Annoyed statement:
I can never read that writing like in ***30
and what's more I told you.
Chaos is found in greatest abundance wherever order is being saught. It always defeats order, because it is better organized.
#83 2007-03-25 08:07:13
- lightning
- Real Member
Offline
Re: *** Problems
they are 10 boy marred too each other?
Zappzter - New IM app! Unsure of which room to join? "ZNU" is made to help new users. c:
#84 2007-03-25 08:28:18
- Devantè
- Real Member
Offline
Re: *** Problems
Firstly, don't post in a 9-month-old thread unless you have something to contribute...I think even you know that 10 boys are not married to each other.
#85 2007-03-25 08:31:31
- lightning
- Real Member
Offline
Re: *** Problems
this is 9 months old? i no that but it's a puzzle it's sopost to be tricky!
Zappzter - New IM app! Unsure of which room to join? "ZNU" is made to help new users. c:
#86 2007-04-25 03:09:28
- Eeyore
- Novice
Offline
Re: *** Problems
ganesh wrote:
***32. A and B are two independent events. The probability that both A and B occur is 1/6 and that of neither of them occuring is 1/3. Find the probability of occurence of A.
Sorry, not enough information to find a unique solution.
I found that P(A) is not equal to P(B). And, since A and B are interchanged "without loss of generality," a.k.a. WOLOG,
then it seems there are two possibilities for P(A).
#87 2007-04-28 03:37:33
- Stanley_Marsh
- Power Member
Offline
Re: *** Problems
To 31
there are 33 numbers which are the multiple of 3 , then the probability of chosing one from 1-100 will be 33/100 , if u chose two number which are not the multiple of 3 , then the probability is (67/100)^2 , then the probability we want is 1- (67/100)^2
To 32 ,
P(A)=x , P(B)=y
xy= 1/6 , (1-x)(1-y)=1/3
y=5/7 ,x= 7/30
Last edited by Stanley_Marsh (2007-04-28 03:42:58)
Numbers are the essence of the Universe
#88 2007-04-28 05:18:22
- mathsyperson
- Moderator
Offline
Re: *** Problems
Or perhaps x=5/7, y=7/30. We don't know, and that's the point Eeyore was making.
Wologs are cute.
Why did the vector cross the road?
It wanted to be normal.
#89 2007-04-28 08:35:40
- Stanley_Marsh
- Power Member
Offline
Re: *** Problems
I check that
P(A on , B off) + P(B on , A off ) + P(A on ,B on ) +P(A off ,B off ) =1
Numbers are the essence of the Universe
#90 2007-09-30 23:32:54
- ganesh
- Moderator
Offline
Re: *** Problems
***33. A Pythagorean triple is a set of three numbers such that the sum of squares of the first two numbers is equal to the square of the third. For example, (3,4,5) is a Pythagorean triple. These formthe lengths of the three sides of a right angled triangle.
Prove that there are an infinite number of primitve Pythagorean triples ( The set (6,8,10) is a Pythagorean triple but not a primitve Pythagorean triple because it is of the form(3n,4n,5n) where n=2 and (3,4,5) is a Pythagorean triple. For example,another primitve Pythagorean triple is(5,12,13)).
Character is who you are when no one is looking.
#91 2007-10-02 17:16:49
- ganesh
- Moderator
Offline
Re: *** Problems
***34. Prove that a rhombus is a cyclic quadrilateral if and only if it is a square.
***35. Prove that a parallelogram is a cyclic quadrilateral if and only if it is rectangle.
Character is who you are when no one is looking.
#92 2007-10-15 00:05:33
- ganesh
- Moderator
Offline
Re: *** Problems
***36. In a get-together, every person present shakes hand with every other person once. If there are 91 handshakes in all, how many persons attended the party?
Character is who you are when no one is looking.
#94 2007-10-15 11:19:52
#95 2007-10-15 22:08:45
- ganesh
- Moderator
Offline
Re: *** Problems
Outstanding, pi man and Jane Fairfax!!!
Character is who you are when no one is looking.
#96 2007-10-20 00:24:03
- ganesh
- Moderator
Offline
Re: *** Problems
37. A vendor has a pair of weighing scales and four weights, the total of all the four weights being 40 kilograms. With the help of any or multiple of these four weights alone and only one wighing on the scale, he can weigh any integral value of weight from 1 to 40 kilograms, both inclusive. How many do these four weights measure?
Character is who you are when no one is looking.
#97 2007-10-31 02:33:41
- ganesh
- Moderator
Offline
Re: *** Problems
38. Can you give a list of 1,000 consecutive non-primes?
Character is who you are when no one is looking.
#98 2007-11-01 02:22:47
- ganesh
- Moderator
Offline
Re: *** Problems
39. How many prime numbers approximately lie between 1 and 1000?
40. What do 1296 and 625 have in common?
Character is who you are when no one is looking.
#99 2007-11-01 02:31:58
#100 2007-11-01 03:12:31
- mathsyperson
- Moderator
Offline
Re: *** Problems
Why did the vector cross the road?
It wanted to be normal.