A statistics pratitioner took a random sample of 30 observations from a population whose standard deviation is 15 and computed the sample mean to be 50. The 90% confidence inverval for the mean will be and .

The 90% confidence inverval for the mean will be 45.509 and 54.491

Step-by-step explanation:

Information given

represent the sample mean

population mean (variable of interest)

represent the sample standard deviation

n= 30 represent the sample size  

Confidence interval

The confidence interval for the mean is given by the following formula:

  (1)

Since the Confidence is 0.90 or 90%, the value of and , the critical value would be

Now we have everything in order to replace into formula (1):

The 90% confidence inverval for the mean will be 45.509 and 54.491

x = 17

step-by-step explanation:

in the given figure, two triangles are inscribed in a circle where ∠bae ≅ ∠dae which makes the side be and de equal so we can write it as:

3x - 24 = x + 10

solving this equation for x to get:

3x - x = 10 + 24

2x = 34

x = 34/2

x = 17

therefore, the value of x = 17.

0.02040816326