Answer:
0.0176
Step-by-step explanation:
This is binomial distribution probability with formula:
[tex]P(x=r)=nCr*p^r *(1-p)^{n-r}[/tex]
Where
n is the total number of trials [here 15 properties]
p is probabilty of success, sell [p = 0.5]
r is what we want [here we want probability of selling less than 4 properties, so r = 4]
Less than 4 means r<4, which means r = 0, r=1, r=2, r=3
We use the formula above and put in 4 different values of r and sum up the result. We will use a binomial calculator online to make it easy. So:
[tex]P(x=0)=15C0*(0.5)^0 *(1-0.5)^{15-0}[/tex] +
[tex]P(x=1)=15C1*(0.5)^1 *(1-0.5)^{15-1}[/tex] +
[tex]P(x=2)=15C2*(0.5)^2 *(1-0.5)^{15-2}[/tex] +
[tex]P(x=3)=15C3*(0.5)^3 *(1-0.5)^{15-3}[/tex]
This is equal to 0.0176
