MATLAB: Make a matrix smaller based on some criteria

Question

I am working with a matrix.

A=[...
20 40 21.5 41
5  21  15  10]

Now, first of all, I want to find out the similar values from row 1. Lets say, the similar values are 20 and 21.5, another pair is 40 and 41. For the each pair, I want to eliminate one column from each pair based on their corresponding column value in the second row. So, I want to eliminate

41
10

and

20
5

because its value in the second row is smaller. The final matrix that I want is

21.5  40
15    21

Thanks in Advance.

Answer 1

row 1 is 20 40 21.5 41 and second row is 5 21 15 10