Answer: Required mean would be 15.
Step-by-step explanation:
Since we have given that
Number of girls G= 75
Number of boys B= 100
Probability that girls smoke = P₂ = 0.20
Probability that girls don't smoke = P'₂=1-0.20=0.80
Probability that boys smoke = P₁ = 0.30
Probability that boys don't smoke = P'₁=1-0.30=0.70
We need to find the mean of the sampling distribution of the difference in the sample proportion of girl smokers and boys smokers.
So, it becomes,
![E[P_1-P_2]=E[P_1]-E[P_2]\\\\=B\times P_1-G\times P_2\\\\=100\times 0.30-75\times 0.20\\\\=30-15\\\\=15](https://tex.z-dn.net/?f=E%5BP_1-P_2%5D%3DE%5BP_1%5D-E%5BP_2%5D%5C%5C%5C%5C%3DB%5Ctimes%20P_1-G%5Ctimes%20P_2%5C%5C%5C%5C%3D100%5Ctimes%200.30-75%5Ctimes%200.20%5C%5C%5C%5C%3D30-15%5C%5C%5C%5C%3D15)
Hence, required mean would be 15.
Answer:
For a line of best fit, it doesn't nessesarily have to land on a point, it just has to be in between them or on them whichever way you choose to do it. And also your second question, yes it is correlation if it lines up with the line and not somewhere else or if there are so many dots that they don't really form a line then it isn't a correlation.
Hope this helps!
8.60 $ because the total was 43 and the family bought 5 of them so 43/5 equals 8.60
Answer:
Choice D
Step-by-step explanation:
(x-1)²
- =(x-1)(x-1)
- =x*x+x*−1+-1*x+-1*-1
- =x²−x−x+1
- =x²−2x+1
Choice D is accurate.
Answer:
2
Step-by-step explanation:
it is always the number before x, or the given variable