(23.01) In a randomized comparative experiment on the effect of dietary calcium on blood pressure, researchers divided 58 healthy white males at random into two groups. One group received calcium; the other, a placebo. At the beginning of the study, the researchers measured many variables on the subjects. The paper reporting the study gives x⎯⎯⎯=113.7 and s = 9.1 for the seated systolic blood pressure of the 29 members of the placebo group. Give a 96% confidence interval for the mean blood pressure in the population from which the subjects were recruited is.

And the 96% confidence is given by (110.06; 117.34)

Step-by-step explanation:

Information given

represent the sample mean

population mean (variable of interest)

s=9.1 represent the sample standard deviation

n=29 represent the sample size  

Confidence interval

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

  (1)

The degrees of freedom are given by:

The Confidence is 0.96 or 96%, the significance is and , and the critical value would be

Replacing the info we got:

And the 96% confidence is given by (110.06; 117.34)

l.ln.lln.k.nkl

step-by-step explanation:

the correct option is 2.

step-by-step explanation:

according to the given information triangle abc is a right angle triangle with right angle at a. segment ab is 5 and segment ac is 7. point d is on segment bc and angles adb and adc are right angles.

it is given that triangles abd, cad, and cba are similar.

two triangles are similar if their corresponding sides are proportional.

in triangle cba, using pythagoras theorem

                      )

triangle abd and cba are similar,

                            (2)

triangle cad and cba are similar,

                      )

using (1), (2) and (3), we get

hence proved.

therefore option 2 is correct.