Question

ou select a marble without looking and then put it back. If you do this 21 times, what is the best prediction possible for the number of times you will pick a marble that is not orange? There are 7 marbles in total, 2 orange marbles and 5 blue marbles

Answer 1

5/7 = non orange marbles
?/21 = chances to pick a non blue
21/7 = 3
5x 3 =15
15/21