## Tuesday, August 21, 2012

### Determine which jar has the heavier marbles in the least amount of weighings

You have 10 jars .Each jar has 100 marbles
9 of the 10 jars -> each marble weighs 1 gram each
last jar -> each marble weights 1.1 grams each
electronic weight scale
- place what you want to weight on it
- hit a button
- get the total weight

find the defective jar ?

Answer:Take 1 marble from jar 1, 2 from jar 2, 3 from jar 3 and so on...so u have 55 marbles in all
Weigh them all together...if total weight is 55.1....then jar 1 is the one with obese marbles...if 55.2..then jar 2...and so on...  again 55.3 can't be the combination of jar 1 and 2 as (.1 +.2 ) since defective jar is only one.

iqbal2907 said...

i can solve in 5 weights.
-------------------------
1. divide in 2 groups of 5-5 jars(2 weights)
2. select the group with heavy weight and divide in 3 group of 2-2-1.
3. weight the group having 2 jars if both have same weight then ans is the rest 1 jar (2 weight)
4. if weight is not same then select the heavier group and weight any jar.(1 weight)

hence total 5 weights. Is it possible to find out the ans in less than 5 weights ??

Anonymous said...

Take 1 marble from jar 1, 2 from jar 2, 3 from jar 3 and so on...so u have 55 marbles in all
Weigh them all together...if total weight is 55.1....then jar 1 is the one with obese marbles...if 55.2..then jar 2...and so on...

therefore just 1 weighing...

Anonymous said...

@anon not true how about reading comes out as 55.3 then its may b combination of 1st and 2nd as (0. +0.2=0.3 ) possible ??

Anonymous said...

Only one of the jars has heavier marbles, so it cannot be a combination of 1st and 2nd.