You have 9 marbles. 8 marbles weigh 1 ounce each, & one
marble weighs 1.5 ounces. You are unable to determine which
is the heavier marble by looking at them. You have a
weighing scale that consists of 2 pans, but the scale is
only good for 2 total weighings.

How can you determine which marble is the heaviest one using
the scale & in 2 weighings?

Answers were Sorted based on User's Feedback



You have 9 marbles. 8 marbles weigh 1 ounce each, & one marble weighs 1.5 ounces. You are unabl..

Answer / guest

Divide 9 marbles into 3 groups of 3 marbles each.

Take any 2 groups and place them on each pan. If they
balance, remove the marbles from the pans, & place any 2 of
the marbles from the remaining unweighed group on the pans,
1 on each pan.

If one is heavier, it is the heavier marble, but if they
balance, the remaining unweighed marble is the heavier one.

If your first weighing does not balance, remove the marbles
from the lighter pan, & place 1 marble on each pan from the
heavier pan. The heavier 1 is the 1.5 ounce marble, but if
they balance, then the marble from the heavy pan from the
first weighing that was not weighed in the second weighing
is the heavy 1.

Is This Answer Correct ?    62 Yes 5 No

You have 9 marbles. 8 marbles weigh 1 ounce each, & one marble weighs 1.5 ounces. You are unabl..

Answer / my name

Divide the 9 marbles into 3 groups: G1, G2, and G3. Weigh G1 with G2. If they balance, then the 1.5 ounce marble is in G3. Otherwise, the 1.5 ounce marble is in the heavier of G1 and G2.

Call the group that definitely contains the 1.5 ounce marble GS. Put one marble from GS in each pan. If they balance, the 1.5 is the member of GS not on a pan. Otherwise, it is the one in the pan on the heavier side.

Is This Answer Correct ?    20 Yes 2 No

You have 9 marbles. 8 marbles weigh 1 ounce each, & one marble weighs 1.5 ounces. You are unabl..

Answer / siddarth chordia

The answer should be arrived in 2 weighings only with worst case scenarios to be considered...
So let us take 3 marbles in each pan

Step 1: If it weighs the same the heavier marble is in the other 3 marbles. else if it differs the heavier side in the balance has the heaver marbles.
Now we have 3 marbles to identify which is the heavier one...

Step 2: From the remaining 3 marbles, keep 1 marble in each pan. If it weighs the same, then the remaining one is the heavier, else which ever side on the balance weighs heavier then that is heavier.

Hope I hit the point of your question with only 2 weighings, to find the answer :)

Is This Answer Correct ?    6 Yes 1 No

You have 9 marbles. 8 marbles weigh 1 ounce each, & one marble weighs 1.5 ounces. You are unabl..

Answer / dheeraj kumar

divide nine marbles into three groups, take any two group and
weight..
condition of scale will be ..
if both pans are same level then the heavy marble will be in
group that you left..
if not in same level then the heavier marble will be in group
in pan which has level down..

apply same procedure on the heavy group..
put two marbles on weighing scale, if both are on same level,
then left one is heavy marble, otherwise heavy one is the
marble which is on pan with level below than another...

Is This Answer Correct ?    4 Yes 3 No

You have 9 marbles. 8 marbles weigh 1 ounce each, & one marble weighs 1.5 ounces. You are unabl..

Answer / hb

I will take 2 marbles on each pan, next time 2 marbles on
each pan. Now answer is
- If all the 8 marbles are weighed same, the heaviest
marble will be the one which is left.
- If in any of the two weighings,the heaviest marble is
will be on the pan which weighs more.

Is This Answer Correct ?    3 Yes 7 No

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