Answer:
The standard deviation of the sample mean differences is _5.23_
Step-by-step explanation:
We have a sample of a population A and a sample of a population B.
For the sample of population A, the standard deviation
is

The sample size
is:
.
For the sample of population B, the standard deviation
is

The sample size
is:
.
Then the standard deviation for the difference of means has the following form:

Finally

The answer is 4 hope this helps
Answer: a=36; b=18
Step-by-step explanation:
1. You know that the sum of two numbers is 54, then, you have:
a+b=54
2. According to the problem, the larger number is 18 more than the sampler number, this can be expressed as following:
a=b+18
3. Then, you must substitute the second equation into the first equation and solve for b:
b+18+b=54
b=18
4. Then the value of a is:
a+18=55
a=36
Answer:
-2x + 7/5
Step-by-step explanation:
(7-10x)/5
=
+ 
= -2x + 7/5