A bag contains 1 red disc, 2 blue discs and 3 green discs.
Ben chooses ta disc at random from the bag. He notes its colour and replaces it. Then he chooses another disc at random from the bag and notes its colour.
1) Calculate the prob that both discs are the same colour?
Is the answer: (1/6)squared + (2/6)squared + (3/6)squared = 7/18
2) Calculate the prob that neither disc is red?
Is the answer: 1 - (1/6)squared = 35/36 ? I fear I might be wrong on this one. But not show why?