Question

During a high school track meet, each race consist of 9 competitors who are randomly assigend lanes from 1 to 9. What is the probability that a runner will draw lanes 1,2, or 3 in the next four races?


Answer: Is the answer is 1/729 or 3/729, please help me. Thanks

Answer 1

first race:
prob(1,2 OR 3) = 3/9 = 1/3
2nd race:
same prob
3rd rac:
same thing
etc

prob(your event) = (1/3)^4 = 1/81