From the problem, there are 10 red balls, 20 yellow balls and 60 orange balls.
The probability of selecting an item is
[tex]p=\frac{\text{event}}{\text{total events}}[/tex]Total events is the number of total balls in the urn.
Total events = 10 + 20 + 60 = 90
The probability of selecting a red ball, the event is the number of red balls, event = 10
[tex]p=\frac{10}{90}=\frac{1}{9}[/tex]The answer is p = 1/9
