155973

I used some counters and a grid that was four squares long and four squares wide.
I placed counters for the saucers first and realised that I couldn't have the same colour counter on the diagonal. So I placed different colour counters on the diagonals. Then I worked out where the remaining counters had to go.
All of the counters for the saucers were placed and checked to see that there were no counters the same colour in each row and column.
I then placed the red cups on one diagonal and the white cups on the other diagonal. I then placed the blue and green cups.
I then checked my work.