There are no results for in the 4- by -4 grid of unit squares shown, two coins will be placed at random such that each coin is in a different unit square. what is the probability that the two coins willl not lie in the same row or column of unit squares? express your answer as a common fraction.

Grid Looks Like This...

APatel Jan 31, 2019

#1**+2 **

Not sure about this...but....

Put one coin in any unit square

Then the second coin can be placed in any of the other 15 unit squares

But.....only 6 of them are either in the same row / column

So.....9 aren't

So......the probability that the two coins do* not *lie in the sane row/column = 9 /15 = 3 / 5

CPhill Jan 31, 2019