https://cis.temple.edu/~latecki/Courses/CIS2033-Spring12/ElementaryProbabilityforApplications/ch3.pdf
Another way of saying this is that if we ignore the outcomes that result in a sum other than 5 or 7, we reduce the sample space from Ω to E = E5 ∪ E7 and the distribution of the first outcome that lands in E follows the conditional probability P(·|E).
https://www.temple.edu/sites/www/files/FINAL%20Campus%20Map%20November%202023.pdf
University Village (privately developed housing) C10, D10–11 Vantage Apartments (privately developed housing) D8–9, E8–10 The View at Montgomery Apartments (privately developed housing) D8–9 Wachman Hall E5 Weiss Hall E7–8, F7–8 Welcome Center/TECH Center D7–8 James S. White Hall