1/(2x2x2x2) for the odds of all roosters, 1/(2x2x2) for 3 roosters or hens, etc. It's been quite a while since I took a course that covered statistics/probability material, but I think it's right. 1/16 of a chance for all roosters or hens.
I’m going with this until mathman sees this! 🤣
1/2 x 1/2 x 1/2 x 1/2 for all four to be roosters.
1/2 x 1/2 x 1/2 x 1/2 = 6.25% (1 rooster)
.5 x .5 x .5 x .5 = 6.25% (1 being the numerator for 1 rooster gives you the correct % there)
2/2 x 1/2 x 1/2 x 1/2 = 2/16 = 12.5% ( 2 roosters)
3/2 x 1/2 x 1/2 x 1/2 = 3/16 = 18.75% (3 roosters)
4/2 x 1/2 x 1/2 x 1/2 = 4/16 = 25% (4 roosters)