# There are nine bags of rice looking alike, eight of which have equal and one is slightly heavier. The weighing balance is of unlimited capacity. Using

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There are nine bags of rice looking alike, eight of which have equal and one is slightly heavier. The weighing balance is of unlimited capacity. Using this balance the minimum number of weighting required to identify the heavier bag is
1. 2
2. 3
3. 4
4. 5

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Correct Answer - Option 1 : 2

Explanation:

Divide 9 bags into three parts.

2,2 and 5 respectively.

If we compare the 2,2 bags on pans of a balance.

We can identify which side is the lighter bag placed.

And then we will need only one more weighing for identifying the faulty bag.

So only two weighings are required.

Alternative solution:

In the case of a weighing balance (i.e. beam balance) the following model can be observed.

1 - 3 → 1 weighing required

4 - 9 → 2 weighings required

10 - 27 → 3 weighings required

28 - 81 → 4 weighings required

And the process will go so on.

As there are nine objects. The minimum number of weighings required will be only 2.