Answer:
Step-by-step explanation:
Given that,
- p ( probability that the child has disease) = 25% = 0.25
- n = number of children = 3
The probability mass function of binomial distribution is,
- (P = X) = (nCx) X (p)^x X (1 - p)^n-x ; x = 0, 1, 2 ,3
- = 3Cx X (0.25)^x X (1 - 0.25)^3-x ; ( n = 3, p = 0.25
a) P ( two will have disease)
p ( X = 2) = 3C2 X (0.250^2 X (1 - 0.25) ^3-2
= 0.1406
b) P ( none will have disease)
p (X = 0) = 3C0 X (0.25)^0 X (1 - 0.25)^3-0
= 0.4219
c) P (neither having the disease nor being a carrier) = 25% = 0.25
The probability that at least one will neither having the disease nor being a carrier ;
P(X> or equals to) = 1 - P(X < 1)
= 1 - P( X = 0)
= 1 - 3C0 X (0.25)^0 X (1 - 0.25)^3-0
= 0.5781
d) p( the first child with the disease will the be 3rd child)
P(X = x) = (1-p)^x-1 X p
p( X= x) = ( 1 - 0.25 )^x -1 X 0.25
for third child = P(X = 3) = (1 - 0.25)^3-1 X (0.25)
= 0.1406
8.9 because you divide and multiply or u can just plug and chug
Answer:
D. 
Step-by-step explanation:
Let be ![y = \Sigma_{i = 0}^{4} \left[5\cdot \left(\frac{1}{3} \right)^{i}\right]](https://tex.z-dn.net/?f=y%20%3D%20%5CSigma_%7Bi%20%3D%200%7D%5E%7B4%7D%20%5Cleft%5B5%5Ccdot%20%5Cleft%28%5Cfrac%7B1%7D%7B3%7D%20%5Cright%29%5E%7Bi%7D%5Cright%5D)
. To find the equivalent expression we must use the following property:
![y = c\cdot \Sigma_{i = 0}^{n} p(x) = \Sigma_{i=0}^{n} [c\cdot p(x)]](https://tex.z-dn.net/?f=y%20%3D%20c%5Ccdot%20%5CSigma_%7Bi%20%3D%200%7D%5E%7Bn%7D%20p%28x%29%20%3D%20%5CSigma_%7Bi%3D0%7D%5E%7Bn%7D%20%5Bc%5Ccdot%20p%28x%29%5D)
(1)
Based on this fact, we find the following equivalence:
Hence, the correct answer is D.
Answer:
C
Step-by-step explanation:
perpecndicular means they intersect in right angle which is 90°, no matter how long lines are.
