Answer: 0.6812
Step-by-step explanation:
Let p be the population proportion of trees are infested by a bark beetle.
As per given: p= 12%= 0.12
Sample size : n= 1000
Number of trees affected in sample = 1000
Sample proportion of trees are infested by a bark beetle. = 
Now, the z-test statistic : 
So, 

Hence, the value of the z-test statistic = 0.6812 .
Answer:
6.8(6.7 – 7.2) – 2(4.6 + 1.2) =-15
Step-by-step explanation:
50+ 7.99 x =y
50+ 7.99 (40)= y
50+319.60= y
369.60=y
50+ 7.99 x =y
50 + 7.99 (50)
50+ 399.50=449.50
6.99(30)=209.70
449.50 + 209.70 =659.2
Answer: 5%
Step-by-step explanation:
The number of employees that took Winter vacation = 75%
The number of employees that took Both winter and summer vacation = 40%
The number that took Neither = 20
The total number of employees (%) =Winter + Summer - Both + Neither = 100%
75%+ Summer - 40%+ 20%= 100%
Solving for Summer = 45%
Now we are interested in the employees that took summer but not winter = Summer only = Summer - Both(i.e. summer overlap with winter) = 45%-40%= 5%
Answer:
A. 46
Step-by-step explanation:
because IJ is 46 also and there both the same size.