Sample size= n= 84
sample mean= x = 107 s
population standard deviation =σ= 11.7
As, population standard deviation is given so we use the estimate:
x(+/-) z(α/2)(σ/√n)
At 99% Confidence interval means significance level is α=1-0.99= 0.01
So,
α/2=0.005
Now, z at α/2=0.005
z= 2.576
Now, by putting values
107(+/-)((2.576)(11.7/√84))
( 107-((2.576)(11.7/√84)), 107+((2.576)(11.7/√84)) )
(103.7, 110.288)
Answer:
Let cost of one bag be Y
8 x Y = $20
So, Y = $2.5
Now cost of 3 bags = 3 x 2.5 = $7.5
Answer:
t= - 48
Step-by-step explanation:
t/8 - 6= -12 add 6 to both side
t/8= -6 multiple by 8
t= -48
Answer:
(0,2)
Step-by-step explanation:
2:4 means one part is 2/(2+4)=1/3 of AB and the other part is 2/3 of AB
Add 1/3 of the distance from -2 to 4. (1/3)(4+2)=2. -2+2=0 The x coordinate is 0
Subtract 1/3 of the distance from 6 to -6, (1/3)6+6)=4 6-4=2 The y coordinate is 2
The point is (0,2)
Answer: 0.923
Step-by-step explanation:
Let A be the event an Internet user posts photos that they have taken themselves, and B be the event an Internet user posts videos that they have taken themselves.
Pew Research Center finds that
P(A)=0.52 P(b)=0.26, and P(A or B)=0.54.
To find : P(A|B)
Since , 
i.e. 
Now, using conditional probability formula ,
Hence, the conditional probability that an Internet user posts photos that they have taken themselves, given that they post videos that they have taken themselves = 0.923
