binomial(16 + 7, 16) 2^(-(16 + 7)) = ((16 + 7)!)/(16! 7! 2^(16 + 7)) = 245157/8388608 ≈ 0.02922 ≈ 1/34.22
(assuming children are independent and male and female are equally likely)
| probability
less than 16 boys | 0.9534
16 or less boys | 0.9827
more than 16 boys | 0.01734
16 or more boys | 0.04657
fraction of boys | 16/(16 + 7) ≈ 0.695652
fraction of girls | 7/(16 + 7) ≈ 0.304348
expected value | 11.5
standard deviation | 2.398
variance | 5.75
11.5
Step-by-step explanation:
On the 8 branch, to the left is 2, and on the right is 4. On the left branch, and on the left, it is 2, and there is a 2 for the 6 branch.
7(200 + 50 + 6) = (7 x 200) + (7 x 50) + (7 x 6) = 1,400 + 350 + 42 = 1,792
