Respuesta :

Answer:

4/91

Step-by-step explanation:

There are a total of 15 marbles.  In the first selection there are 15 marbles and 6 are blue.  That would be 6/15.

Since we are not replacing marbles, we now have 14 marbles and we want to select one of the 5 white marbles.  That would be 5/14.

Lastly we now only have 13 marbles and of those we want to select one of the 4 red ones.  That would be 4/13.

Now we take these 3 fractions and multiply them together.

6/15(5/14)(4/13).  I am going to try to make this a little easier and see if I can find any factors that any top number shares with any bottom number.

I see 5 on the top shares a common factor with 15 on the bottom.  I will divide these numbers by 3, so now I have

6/3(1/14)(4/14).  I think that I can do better than that.  I see that 6 on the top and 3 on the bottom share a common factor of 3.  I will divide both of these numbers by 3.  Which will give me:

2/1(1/14)(4/13) I see a 4 on top and a 14 on the bottom.  Those are both divisible by 2 so, I will divided them both by 2 and that leaves me with

2/1(1/7)(2/13)  That is a lot easier, now I will just multiple the top numbers and multiply the bottom numbers to get

4/91