Answer:
1 : 3000
Step-by-step explanation:
Given that:
Scale measurement as following:
4 centimeters are equal to 120 meters.
To find:
The scale factor = ?
Solution:
First of all, let us learn about the definition of scale factor.
Scale factor means 1 unit on scale is equal to what length of actual measurement.
We are given that 4 cm on scale is equal to 120 meters of actual length.
We need to find nothing but how much 1 cm of scale is equal to actual length.
4 cm of scale = 120 meters or 12000 cm of actual length
Dividing by 4 on both sides, we get:
= 1 cm of scale = 
= 3000 cm of actual length
Therefore, the scale factor is <em>1 : 3000</em>
The 90% confidence interval for the population mean of the considered population from the given sample data is given by: Option C: [130.10, 143.90]
<h3>
How to find the confidence interval for population mean from large samples (sample size > 30)?</h3>
Suppose that we have:
- Sample size n > 30
- Sample mean =
- Sample standard deviation = s
- Population standard deviation =
- Level of significance =
Then the confidence interval is obtained as
- Case 1: Population standard deviation is known
- Case 2: Population standard deviation is unknown.
For this case, we're given that:
- Sample size n = 90 > 30
- Sample mean = = 138
- Sample standard deviation = s = 34
- Level of significance = = 100% - confidence = 100% - 90% = 10% = 0.1 (converted percent to decimal).
At this level of significance, the critical value of Z is: 
= ±1.645
Thus, we get:
![CI = \overline{x} \pm Z_{\alpha /2}\dfrac{s}{\sqrt{n}}\\CI = 138 \pm 1.645\times \dfrac{34}{\sqrt{90}}\\\\CI \approx 138 \pm 5.896\\CI \approx [138 - 5.896, 138 + 5.896]\\CI \approx [132.104, 143.896] \approx [130.10, 143.90]](https://tex.z-dn.net/?f=CI%20%3D%20%5Coverline%7Bx%7D%20%5Cpm%20Z_%7B%5Calpha%20%2F2%7D%5Cdfrac%7Bs%7D%7B%5Csqrt%7Bn%7D%7D%5C%5CCI%20%3D%20138%20%5Cpm%201.645%5Ctimes%20%5Cdfrac%7B34%7D%7B%5Csqrt%7B90%7D%7D%5C%5C%5C%5CCI%20%5Capprox%20138%20%5Cpm%205.896%5C%5CCI%20%5Capprox%20%5B138%20-%205.896%2C%20138%20%2B%205.896%5D%5C%5CCI%20%5Capprox%20%5B132.104%2C%20143.896%5D%20%5Capprox%20%5B130.10%2C%20143.90%5D)
Thus, the 90% confidence interval for the population mean of the considered population from the given sample data is given by: Option C: [130.10, 143.90]
Learn more about confidence interval for population mean from large samples here:
brainly.com/question/13770164
Answer:
i am very confused...
Step-by-step explanation:
but im going to ask that n= (3,2)
<h3>
Answer: 81</h3>
Work Shown:
x = number of cats
(4 cats)/(5 dogs) = (x cats)/(45 dogs)
4/5 = x/45
4*45 = 5x
180 = 5x
5x = 180
x = 180/5
x = 36
There are 36 cats and x+45 = 36+45 = 81 cats and dogs total.
20 * (30 ÷ 65) = <span>9.23076923077</span>
