Answer:
The answer us B y= -8/7x -18/7
<h2>
Answer with explanation:</h2>
Given : Sample size 
Sample mean : 
Sample standard deviation : 
Let
be the population mean of "like" ratings of male dates made by the female dates.
As per question ,
Null hypothesis : 
Alternative hypothesis :
, It means the test is a one-tailed t-test. ( we use t-test when population standard deviation is unknown.)
Test statistic:

For 0.05 significance and df =188 (df=n-1) p-value = .001582. [By t-table]
Since .001582< 0.05
Decision: p-value < significance level , that means there is statistical significance, so we reject the null hypothesis.
Conclusion : We support the claim at 5% significance that t the population mean of such ratings is less than 8.00.
Answer:
3:2
Step-by-step explanation:
The ratio of boys to girls will be 12:8
But, this can be simplified, since both numbers are divisible by 4.
12/4 = 3
8/4 = 2
So, the simplified ratio of boys to girls is 3:2
The z-statistic can be calculated as the difference in the population mean and sample mean divided by the standard error. The standard error can be calculated as the standard deviation divided by square root of sample size. The standard error:
SE = 12/ sqrt(20) = 2.68
The z-statistic: (195 -208) 2.68 = -4.86