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Guest Message by DevFuse
 

BMAD

Member Since 18 Feb 2013
Offline Last Active Today, 06:07 AM
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Topics I've Started

Light-bulb Problem

17 June 2013 - 10:15 PM

This is a modified version of the famous light-bulb problem.  

 

There are three switches in the hallway.  turning on the switches in different combinations cause different light-bulbs in the room to turn on. There are six light-bulbs and from turning on all of the possible combinations, each light-bulb is turned on at most twice (in other words there are only two ways to turn on a light-bulb).  We need to map the switches to the light-bulbs.  

 

The only things we know is that flicking 1 switch causes 1 light-bulb to turn-on, flicking 2 switches causes 2 to turn-on, and flicking all 3 cause three light-bulbs to turn-on and if a switch turns on a light-bulb, that switch must be on to turn it on again (even if flicking 2 switches).

 

What is the fewest number of 'tests' needed to effectively map the light-bulbs to the switches?


A baby, a mother, and a dog

17 June 2013 - 09:55 PM

How much does the baby weigh if the mother weighs 100 pounds more than the combined weight of the baby and the dog, and the dog weighs 60 percent less than the baby?

 

Attached File  weigh-the-baby.jpg   11.72KB   9 downloads


Modified Deal or No Deal

17 June 2013 - 09:53 PM

The Basics of Modified Deal or No Deal:

 

There are ten boxes labeled 1 through 10.

The boxes have a check in them worth from .01 to 10,000,000 dollars as such $.01, $.10, $1.00, $10.00, $100.00, $1000.00, $10,000, $100,000, $1,000,000, and $10,000,000).  

The amounts are randomly placed in the marked boxes.

The player first selects their chosen box.

 

The game proceeds as folllows:

Round 1:

The player select 2 boxes to be revealed

--An offer is made to the player, if the player agrees, the game is over.

Round 2:

if not- the player selects 2 boxes to be revealed

--An offer is made to the player, if the player agrees, the game is over.

Round 3:

if not- the player selects 2 boxes to be revealed

--An offer is made to the player, if the player selects, the game is over.

Round 4:

if not- the player selects 2 boxes to be revealed

--An offer is made to the player, if the player selects, the game is over.

Round 5:

if not- the player's chosen box is revealed and they take the prize.

 

The individual making the offer to the player is known as the banker.  It is well-known, in this game, that the banker offers 85% below the median of the boxes for the first round and increases that percentage by 5% of the median of the remaining boxes each later round.  A player was made the following offers

 

Round 1: 4,675.00

Round 2: 4,950.00

Round 3: 5,225.00

Round 4: 5,500.00

 

What boxes were chosen each round?

Should the player take the offer?

 

 

 

 

 

 

 


Three towns revisited

13 June 2013 - 12:13 AM

three towns are located such that they are equal distant to the center of a park.  What is longer, walking from one city to the other two or walking to the park and back?

 

note: by taking straight paths


Happy Harold's Five Floor Elevators

09 June 2013 - 04:23 AM

The owner of the Party Hotel chain, Happy Harold, enjoyed a very good business, renting his entire hotel for group parties.  Harold also owned an elevator business and (of course) supplied his hotel with his own elevators. Harold was a bit frugal, however, and only put six elevators in his hotel. To make matters worse, his elevator designers hadn't passed the demonstration phase of their designs before Harold put them to use and each elevator could stop at only five floors.
 
Harold's guests found it an intriguing aspect of the hotel that no more than two elevator rides were needed to reach any floor of the hotel. What was the maximum number of floors in the hotel? Can you show a possible configuration for the elevators?
 
Harold's guests said it sometimes took too long to wait for an elevator on the floors that only had one elevator stop. Harold built his next hotel such that every floor had two elevators stop at it, and no two elevators stopped at the same two floors. Again, no more than two elevator rides were needed to reach any other floor. What is the maximum number of floors in this new hotel? Can you show a possible configuration for the elevators?
 
Although the guests found the multiple elevator rides unique, they eventually tired of needing to switch. Harold built his next hotel such that only one elevator ride was necessary to reach any other floor. What is the maximum number of floors in this new hotel? Can you show a possible configuration for the elevators?
 
Harold realized that his profits kept getting smaller, but he never invested in more elevator doors. How many elevators would he need to build to the height of his first hotel, but meet the requirements of the last?