Answer:
b. Student-t with 48 degrees of freedom
Step-by-step explanation:
For this case we need to use a Two Sample t Test: equal variances.
Assumptions
When running a two-sample equal-variance t-test, the basic assumptions are "that the distributions of the two populations are normal, and that the variances of the two distributions are the same".
Let
and
be the sample means of two sets of data of size
and
respectively. We assume that the distribution's of x and y are:


Both are normally distributed but without the variance equal for both populations.
The system of hypothesis can be:
Null hypothesis: 
Alternative hypothesis: 
We can define the following random variable:

The random variable t is distributed
, with the degrees of freedom 
And the pooled variance can be founded with the following formula:

So on this case the best answer would be :
b. Student-t with 48 degrees of freedom
Answer:
Step-by-step explanation:
<u>Given:</u>
- Initial population = 6.08 billion
- Increase rate = 1.5% or 0.015 times per year
Time passed = 2017 - 2000 = 17 years
<u>Population in 2017:</u>
- P = 6.08*(1 + 0.015)^17 = 7.8 billion
Answer:
180
Step-by-step explanation:
Answer:
1.) Drawing a king or a queen.
Step-by-step explanation:
1.) Drawing a king or a queen.
You cannot get a king and a queen at the same time= mutually exclusive
2.) Drawing a club or a black card.
King of clubs is both a club and a black card
3.) Drawing a king or a heart.
king of hearts is both a heart and a king
4.) Drawing a face card or a heart
queen of hearts is a heart and a face card
Answer:
there both different the only same number is four
Step-by-step explanation: