Answer:
natural no.s are those no.s which don't have any negative integer or any fractional value
they begin zero and so on
I believe your length would be 8, because -3 to get to 0 is 3 then after that you still have 5 so you add them and get 8
F(x,n,p)=C(n,x)p^x*(1-p)^(n-x)
n=9, p=0.8 =>
f(x,9,0.8)=C(9,x)0.8^x*(0.2)^(9-x)
The function f(x,9,0.8) is then calculated using the above formula
x f(x)
0 0.0000001 0.0000182 0.0002953 0.0027534 0.0165155 0.0660606 0.1761617 0.3019908 0.3019909 0.134218
Check Sum f(x), [x=0,9] = 1.0 ok
