Hi,

Calculating the probability as stated below, I cannot make it work because by my calculations it is undefined where n=8 and x=0

p=0.20

n = 8

x < 2

P(x <2)= P(x=0)+P(x=1)

= 8/0*(0.20)^0*(1-0.20)^8 + 8/1*(0.20)^1*(1-0.20)^7

What is wrong with my workings?

Thanks

Splint

Update: Would it be more appropriate to write it as 1-(P((X=2)+(X=3)+(X=4)+(X=5)+(X=6)+(X=7)+(X=8))