3 red marbles and 4 blue marbles in a bag probability

There are 7 marbles in total (3 red, 4 blue)

The possibility of the first marble being blue is 4/7. We now have just 6 marbles in this bag which are (3 red, 3 blue).

The possibility of the next following number will be blue which is 3/6.

Now that we’ve finished putting the numbers in this situation what we now need to do is form an equation to solve this problem.

So for the following numbers we must now do blue by multiplying the two chances.

4/7(3/6)=12/42=2/7 which is ultimately 28.6%.

Is that all you want? Or is there something you want me to do?