In an experiment, 200 children are arranged in 10 different rows, where each row contains 20 children. As a result, 20 columns are formed. From each of those columns, the shortest one is selected and from those 20 children, the tallest one is tagged X. These children now return to their initial places.
Now, the tallest child from each row is selected and the shortest from them is tagged Y.
Can you tell which one from the two (X and Y) is taller?
Solution:
There can be three cases for this question.
1) X and Y are present in the same row.
In this case, Y will be the tallest in the row => Y is taller than X.
2) X and Y are present in the same column.
In this case, X will be the shortest of the column => Y is taller than X.
3) X and Y are present in different rows and different columns. Suppose that the child standing in X’s column and Y's row is Z. Then:
Y is taller than Z and Z is taller than X => Y is taller than X.
Therefore, in any of the above cases, Y is taller than X.