Answer: 15.08
Step-by-step explanation:
The test statistic for difference between two population means is given by :-
![z=\dfrac{\overline{X}-\overline{Y}}{\sqrt{\dfrac{\sigma_x^2}{n_x}+\dfrac{\sigma_y^2}{n_y}}}](https://tex.z-dn.net/?f=z%3D%5Cdfrac%7B%5Coverline%7BX%7D-%5Coverline%7BY%7D%7D%7B%5Csqrt%7B%5Cdfrac%7B%5Csigma_x%5E2%7D%7Bn_x%7D%2B%5Cdfrac%7B%5Csigma_y%5E2%7D%7Bn_y%7D%7D%7D)
Given : State A State B
Sample size 80 50
Mean interest rate (%) 4.0 4.5
Population variance 0.04 0.03
Then , the test statistic for difference between two population means will be :-
![z=\dfrac{4.0-4.5}{\sqrt{\dfrac{0.04}{80}+\dfrac{0.03}{50}}}\\\\\Rightarrow z=15.0755672289\approx15.08](https://tex.z-dn.net/?f=z%3D%5Cdfrac%7B4.0-4.5%7D%7B%5Csqrt%7B%5Cdfrac%7B0.04%7D%7B80%7D%2B%5Cdfrac%7B0.03%7D%7B50%7D%7D%7D%5C%5C%5C%5C%5CRightarrow%20z%3D15.0755672289%5Capprox15.08)
Hence, the value of the test statistic will be 15.08 .
For this case we first write the equation of which we will use:
I (db) = 10log (l / l)
We substitute the value of l.
We have then:
l = 10 ^ 8lo
Substituting in the given equation:
I (db) = 10log ((10 ^ 8lo) / lo)
Rewriting:
I (db) = 10 * log (10 ^ 8)
I (db) = 80
Answer:
I (db) = 80
option 4
Step-by-step explanation:
the cost of 8 books at $4 each
=》8 × 4 = $ 32
the cost of x books at $4 each
=》x × 4 = $ 4x
the cost of 5 books at $x each
=》5 × x = $ 5x
Answer:
Yes
Step-by-step explanation:
Remember in order for the rates to be proportional it has to have a constant rate of change and it has to go through the origin if graphed
For one this has a constant rate of change which is 3 dollars per 25 messages
Now we just have to find out if it would go through the origin (0,0)
To do so we subtract 3 dollars and then 25 messages
6-3=3
50 - 25 =25
then again 25-25=0
3-3=0
concluding that (0,0) is a solution
Thus meaning that this is a proportional relationship
The chance is 1 out of 3. The fraction is ⅓ or 1 over three.
It is tiring to type this again but... hope this helps.