Respuesta :

Answer:

The part of the stock owned by others is  3/18

Step-by-step explanation:

Rob owns  5/9 of the stock

And Talia half as much as Rob then Talia has:

(5/9) ÷ 2   = 5/18 of the stock

So Rob and his sister they both have  

5/9 + 5/18   =  ( 10 + 5 ) / 18   ⇒  15/18

And the part of the stock owned by others is:

The total stock in term of fraction is  18/18  o     1  or 100 %

Then  (18/18) - (15/18) = 3/18