Hello, thank you for taking the time to post your question!
The general framework that you want to use here for computing probability is that you want to find
Probability = outcomes that meet the criteria / total number of possible outcomes
For the total on this one you would need all 7 people to make the same combination choice … meaning that you want to compute combination of 6, choose 2 and then raise that to the power of 7.
That ends up being C(6,2) = 15, then 15^7 possible outcomes
Next then we want to find the odds of it being a favorable outcome, which you can again compute using C(6,2) = 15
That makes the end computation
probability = 15/15^7 = 1/15^6 = 1 / 11,390,625, meaning that it would be extremely unlikely for this situation to happen in practice! which intuitively makes sense if you think about how rare of an occurrence this would be.
Hopefully that gets you moving in the right direction! Feel free to reach out for a lesson if you have any questions about the process to solve beyond that! :)
