Post by tarathian123 on May 8, 2017 9:51:58 GMT
Weight problems? Try this:
Mr Smith has lots of pound coins, ten boxes in all. Each box contains 100 pound coins, but one box contains coins which are all counterfeit and are slightly lighter, 1/16 of an ounce lighter to be exact.
The problem lies in the fact that they all look identical, the only way to tell them apart is to weigh them.
Mr Smith knows the correct weight for a box, but how many weighings are required to determine which box contains the counterfeit ones? Give reasoning for your solution.
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Ponder this:
You can imagine an arrow in flight, toward a target. For the arrow to reach the target, the arrow must first travel half of the overall distance from the starting point to the target. Next, the arrow must travel half of the remaining distance.
For example, if the starting distance was 10m, the arrow first travels 5m, then 2.5m, 1.25m, 0.625m, 0.3125m and so on.
If you extend this concept further, you can imagine the resulting distances getting smaller and smaller. Will the arrow ever reach the target?
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My final teaser for the day:
Band tempo?
There is a concert that starts in just 17 minutes and all four of the band members must all cross a bridge to get there. The members begin on the same side of the bridge and you must help them to get across to the other side.
Due the age of the bridge, a maximum of two people can cross at one time. To make matters worse, it is night-time and there is only one torch. The torch is always required when crossing the bridge and the torch must be walked back and forth, it cannot be thrown, etc. Each band member walks at a different speed and a pair must walk together at the rate of the slower man:
Alan takes 1 minute to cross
Bill takes 2 minutes to cross
Carl takes 5 minutes to cross
Dave takes 10 minutes to cross
For example, if Alan and Dave walk across first, it takes them 10 minutes to cross. If Alan then returns with the torch, a total of 11 minutes will have passed. There is no trick behind this, it is the simple movement of resources in the appropriate order. Really a variation of the Fox/Chicken/Seed riddle.
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Mr Smith has lots of pound coins, ten boxes in all. Each box contains 100 pound coins, but one box contains coins which are all counterfeit and are slightly lighter, 1/16 of an ounce lighter to be exact.
The problem lies in the fact that they all look identical, the only way to tell them apart is to weigh them.
Mr Smith knows the correct weight for a box, but how many weighings are required to determine which box contains the counterfeit ones? Give reasoning for your solution.
-------------------
Ponder this:
You can imagine an arrow in flight, toward a target. For the arrow to reach the target, the arrow must first travel half of the overall distance from the starting point to the target. Next, the arrow must travel half of the remaining distance.
For example, if the starting distance was 10m, the arrow first travels 5m, then 2.5m, 1.25m, 0.625m, 0.3125m and so on.
If you extend this concept further, you can imagine the resulting distances getting smaller and smaller. Will the arrow ever reach the target?
------------------------
My final teaser for the day:
Band tempo?
There is a concert that starts in just 17 minutes and all four of the band members must all cross a bridge to get there. The members begin on the same side of the bridge and you must help them to get across to the other side.
Due the age of the bridge, a maximum of two people can cross at one time. To make matters worse, it is night-time and there is only one torch. The torch is always required when crossing the bridge and the torch must be walked back and forth, it cannot be thrown, etc. Each band member walks at a different speed and a pair must walk together at the rate of the slower man:
Alan takes 1 minute to cross
Bill takes 2 minutes to cross
Carl takes 5 minutes to cross
Dave takes 10 minutes to cross
For example, if Alan and Dave walk across first, it takes them 10 minutes to cross. If Alan then returns with the torch, a total of 11 minutes will have passed. There is no trick behind this, it is the simple movement of resources in the appropriate order. Really a variation of the Fox/Chicken/Seed riddle.
=============