![]() |
![]() ![]() |
![]() |
CP |
![]()
Post
#1
|
![]() Moderator ![]() ![]() Member No.: 309 Group: Super Moderator Posts: 2,836 Topics Started: 59 Joined: 22-Jun-04 Last seen online: Mon, 13 Feb 2023 10:37 pm User's local time: Mon, 14 Apr 2025 2:28 pm Green Water: Yes Country: Singapore ![]() |
For primary school children:
12 indentical billiard balls,one slightly heavier than the rest.Using a balance not more than 3 times,describe the steps involved to determine the heavier ball. (The balance is the "Barisan Nasional" logo type). For Rafflesgoldians: 12 identical billiard balls,one is different from the rest.We dont know whether it is heavier or lighter.Using the same balance,find the odd billiard ball in not more than 3 tries. |
RBT |
![]()
Post
#2
|
![]() Ordinary ![]() Member No.: 152 Group: Member Posts: 90 Topics Started: 2 Joined: 25-Mar-04 Last seen online: Tue, 23 Aug 2011 1:40 am User's local time: Mon, 14 Apr 2025 2:28 pm Green Water: Yes Country: Singapore ![]() |
Split pack into 6balls per side of the scale.1st try 6 n 6 take heavier set n split again
2nd try split these 6 into 3s n weigh,take heavier 3 n go to 3rd try.On the last try split into one an a one an a one.......weigh two ones n hold one ones in your hand...hehe...by now u should know which one of the ones is the heavy one!!!! |
CP |
![]()
Post
#3
|
![]() Moderator ![]() ![]() Member No.: 309 Group: Super Moderator Posts: 2,836 Topics Started: 59 Joined: 22-Jun-04 Last seen online: Mon, 13 Feb 2023 10:37 pm User's local time: Mon, 14 Apr 2025 2:28 pm Green Water: Yes Country: Singapore ![]() |
Heh heh heh what abt the second question.
![]() I will give 3 kowtows to the first person that cracks it. The answer to the first question can be put this way: 1st try - 6/6.Take heavier 6 for 2nd try 2nd try -3/3. Take heavier 3 for 3rd try 3rd try - 1/1 .If it tilts,you have the answer.If it balances,it is the ball you have not tried. Another solution for the 1st question: 1st try - 4/4.If it balances,you are left with 4 balls and 2 tries so its easy from there. If it tilts,you are also left with 4 balls and 2 tries so its easy from there as well. |
Jos Nana |
![]()
Post
#4
|
![]() (Retired) ![]() Member No.: 21 Group: Honorary Member Posts: 152 Topics Started: 3 Joined: 25-Nov-03 Last seen online: Sun, 18 Oct 2009 10:01 am User's local time: Mon, 14 Apr 2025 2:28 pm From: Singapore Green Water: No Country: Singapore ![]() |
First Weighing, 4/4 on each side :
If equal, use the 8 balls that has already being weighed as sample. Weigh 3 of the remaining 4 balls against 3 samples. If equal, the remaining one is the odd ball. If unequal, you would already have acertained that the odd ball is heavier or lighter in the second weighing. The last weighing of any 2 of the 3 odds balls will determined the odd ball out. If unequal after the first weighing, say Right pan down, Left pan up.... The remaining 4 balls are now samples. Take 1 ball each out of Right pan & left pan. Marked and move 2 balls from right pan to left pan. Marked and move 1 ball from left pan to right pan.Right pan now has 2 balls while left pan has 4 balls. Top up right pan with 2 of the 4 determined sample balls. Commence weighing no 2. This will give you 3 possible scenarios : A. The balance becomes equal. This means that the 2 balls removed from each side are the odd balls. The last weighing of one of these 2 balls against the 1 of the 10 samples will determined the odd ball. B. The balance changes to Right pan up, Left pan down. It means either the 2 balls that was being moved over from the right pan to the left pan are heavier or the 1 ball the was being send from left pan to right pan is lighter. Weigh the 2 heavier balls. If equal, that means the odd ball send from left pan to right pan is the odd ball cos being lighter thus altering the balance position. If unequal, the heavier ball is the odd ball cos only a heavier ball is able to alter the balance position. C. The balance position remains the same. ie. Right down, Left up. It means either the 1 retained ball from right pan is heavier or the 2 retained ball on the left pan is lighter. Weigh the 2 lighter balls. If equal, that means odd ball is the one retained on the right pan. If unequal, the lighter ball is the odd ball. KNN sibei cheep..... |
CP |
![]()
Post
#5
|
![]() Moderator ![]() ![]() Member No.: 309 Group: Super Moderator Posts: 2,836 Topics Started: 59 Joined: 22-Jun-04 Last seen online: Mon, 13 Feb 2023 10:37 pm User's local time: Mon, 14 Apr 2025 2:28 pm Green Water: Yes Country: Singapore ![]() |
As promised.....
JOS NANA ![]() ![]() ![]() |
CP |
![]()
Post
#6
|
![]() Moderator ![]() ![]() Member No.: 309 Group: Super Moderator Posts: 2,836 Topics Started: 59 Joined: 22-Jun-04 Last seen online: Mon, 13 Feb 2023 10:37 pm User's local time: Mon, 14 Apr 2025 2:28 pm Green Water: Yes Country: Singapore ![]() |
This is simpler so no kowtows:
10 bottles of identical looking pills,all medicine except one of the bottle which is poison.There are hundreds of pills in each bottle. Each medicine pill weights 10g,whereas each poison pill weighs 11g. You are given a weighing machine capable of measuring weights to the accuracy of the nearest 1g.Using the weighing machine only once,determine the poison bottle. |
Jos Nana |
![]()
Post
#7
|
![]() (Retired) ![]() Member No.: 21 Group: Honorary Member Posts: 152 Topics Started: 3 Joined: 25-Nov-03 Last seen online: Sun, 18 Oct 2009 10:01 am User's local time: Mon, 14 Apr 2025 2:28 pm From: Singapore Green Water: No Country: Singapore ![]() |
QUOTE(cpiw2002 @ Tue, 23 Nov 2004 2:04 pm) This is simpler so no kowtows: 10 bottles of identical looking pills,all medicine except one of the bottle which is poison.There are hundreds of pills in each bottle. Each medicine pill weights 10g,whereas each poison pill weighs 11g. You are given a weighing machine capable of measuring weights to the accuracy of the nearest 1g.Using the weighing machine only once,determine the poison bottle. Dun spoil the fun. Let someone else try to crack this one. |
Allan |
![]()
Post
#8
|
![]() Co-Founder ![]() Member No.: 3 Group: Administrator Posts: 696 Topics Started: 42 Joined: 21-Nov-03 Last seen online: Tue, 12 Apr 2005 7:12 pm User's local time: Mon, 14 Apr 2025 2:28 pm From: Virtual Singapore Green Water: Yes Country: Singapore ![]() |
Explain this one.
![]() ![]() |
Jos Nana |
![]()
Post
#9
|
![]() (Retired) ![]() Member No.: 21 Group: Honorary Member Posts: 152 Topics Started: 3 Joined: 25-Nov-03 Last seen online: Sun, 18 Oct 2009 10:01 am User's local time: Mon, 14 Apr 2025 2:28 pm From: Singapore Green Water: No Country: Singapore ![]() |
Optical illusion. The 2 bisecting angles are not the same but close. The media presentation covers this up and the 0.2 length extension.
|
CP |
![]()
Post
#10
|
![]() Moderator ![]() ![]() Member No.: 309 Group: Super Moderator Posts: 2,836 Topics Started: 59 Joined: 22-Jun-04 Last seen online: Mon, 13 Feb 2023 10:37 pm User's local time: Mon, 14 Apr 2025 2:28 pm Green Water: Yes Country: Singapore ![]() |
Parts from the first pic will not fill into the second pic.If the second pic is blown up,you will see gaps in between and the total area of the gaps will add up to 1 unit, the diff. in area bet. the first and second pic.
|
CP |
![]()
Post
#11
|
![]() Moderator ![]() ![]() Member No.: 309 Group: Super Moderator Posts: 2,836 Topics Started: 59 Joined: 22-Jun-04 Last seen online: Mon, 13 Feb 2023 10:37 pm User's local time: Mon, 14 Apr 2025 2:28 pm Green Water: Yes Country: Singapore ![]() |
I have a 90% success rate of reading your minds.
Follow the steps then scroll all the way down for my guess. 1)Think of any number between 1 and 10. 2)Multiply the number that you think by 9. 3)If your answer is two digits,add the digits up. If it is single digit,leave it as it is. 4)Subtract 4 from the number you obtained from step (3) for your final answer. 5)Replace your final answer with an alphabet.If final answer is 1 replace with A,if its 2 replace with B, if its 3 replace with C and so on..... 6)Think of an animal that begins with the alphabet that you just obtained. Ready?Now scroll down for my guess on what you are thinking. > > > > > > > < < > > > > > > > > > > > > > > > < < < > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > < < < < < < < < < < > .> > > > > > ...............ELEPHANT? |
CP |
![]()
Post
#12
|
![]() Moderator ![]() ![]() Member No.: 309 Group: Super Moderator Posts: 2,836 Topics Started: 59 Joined: 22-Jun-04 Last seen online: Mon, 13 Feb 2023 10:37 pm User's local time: Mon, 14 Apr 2025 2:28 pm Green Water: Yes Country: Singapore ![]() |
Count the number of 'F's in the following text:
FINISHED FILES ARE THE RE- SULT OF YEARS OF SCIENTIF- IC STUDY COMBINED WITH THE EXPERIENCE OF YEARS Managed it? Scroll down only after you have counted them! Don't cheat. OK? How many? Three? Four? Wrong, there are six - no joke! Read again! FINISHED FILES ARE THE RE- SULT OF YEARS OF SCIENTIF- IC STUDY COMBINED WITH THE EXPERIENCE OF YEARS The reasoning is the brain cannot process the word "OF". Incredible or what? Anyone who counts all six 'F' on the first go is a genius, Three is normal |
goldrush |
![]()
Post
#13
|
![]() RG Doc.com ![]() ![]() Member No.: 319 Group: Forum Doctor Posts: 3,327 Topics Started: 377 Joined: 25-Jun-04 Last seen online: Fri, 03 Jan 2025 2:54 pm User's local time: Mon, 14 Apr 2025 2:28 pm Green Water: No Country: Singapore ![]() |
Yes you are right CP
somehow my brain cannot read "of" but that's becos mine is programmed to read only "FO" ![]() ![]() ![]() |
![]() ![]() |
![]() |
Lo-Fi Version | Time is now: 14-Apr-25 2:28 pm |