The police department of a city with a population of 250000 wants to know how many residents wear their seatbelts regularly. which sample size would make the study most reliable? a. 2500 b. 250 c. 5 d. 25

Option A is correct.

Step-by-step explanation:

Given:

Population of the city is 250,000

Police department wants to know how many residents wear their seat belts regularly.

To find: Sample size for the study which make it most reliable.

Most reliable study means study which produce most accurate result.

We know that a study can produce most accurate result only when the sample size if as possible large.

So, among given options Only Possible Sample Size is 2500

Therefore, Option A is correct.

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4