🍁Nine Ancient Obelisks

A problem from Yashur. In Asuga, there are **x** residents, of whom **y** are adults, and **z** of them are men of "traditional orientation." Of these men, **t** believe that they didn't find their "bundle of joy" in the trash and don't intend to shove it anywhere. Find the probability that Insho will achieve his goal of 10,000 "bundles of joy" in **n** years...