Answer:
(a) 0.28347
(b) 0.36909
(c) 0.0039
(d) 0.9806
Step-by-step explanation:
Given information:
n=12
p = 20% = 0.2
q = 1-p = 1-0.2 = 0.8
Binomial formula:

(a) Exactly two will be drunken drivers.



Therefore, the probability that exactly two will be drunken drivers is 0.28347.
(b)Three or four will be drunken drivers.


Using binomial we get



Therefore, the probability that three or four will be drunken drivers is 0.3691.
(c)
At least 7 will be drunken drivers.

![P(x\leq 7)=1-[P(x=0)+P(x=1)+P(x=2)+P(x=3)+P(x=4)+P(x=5)+P(x=6)]](https://tex.z-dn.net/?f=P%28x%5Cleq%207%29%3D1-%5BP%28x%3D0%29%2BP%28x%3D1%29%2BP%28x%3D2%29%2BP%28x%3D3%29%2BP%28x%3D4%29%2BP%28x%3D5%29%2BP%28x%3D6%29%5D)
![P(x\leq 7)=1-[0.06872+0.20616+0.28347+0.23622+0.13288+0.05315+0.0155]](https://tex.z-dn.net/?f=P%28x%5Cleq%207%29%3D1-%5B0.06872%2B0.20616%2B0.28347%2B0.23622%2B0.13288%2B0.05315%2B0.0155%5D)
![P(x\leq 7)=1-[0.9961]](https://tex.z-dn.net/?f=P%28x%5Cleq%207%29%3D1-%5B0.9961%5D)

Therefore, the probability of at least 7 will be drunken drivers is 0.0039.
(d) At most 5 will be drunken drivers.



Therefore, the probability of at most 5 will be drunken drivers is 0.9806.
Answer:
She Jen djzksndhdi
Step-by-step explanation:
Money,temperature, sea level,
Answer:
Yes
Step-by-step explanation:
You can check whether the ratios form a proportion, by setting one piece of the ratios as x
Thus, we can use the equation 4/3.2=22/x.
From this, we get 4x=70.4.
Solving for x gives us 17.6.
Answer:
x^2 -14x +49
( x-7)^2
Step-by-step explanation:
x^2 -14x
We are completing the square
Take the coefficient of x
-14
Divide by 2
-14/2 = -7
Square it
(-7)^2 = 49
Add it
x^2 -14x +49
Take the -7
( x-7)^2