A sociologist wishes to estimate the average number of automobile thefts in a large city per day within 2 automobiles. He wishes to be 99% confident, and from a previous study the standard deviation was found to be 4.2. How many days should he select to survey

So the answer for this case would be n=30 rounded up to the nearest integer

Step-by-step explanation:

Information given

the margin of error desired

standard deviation from previous studies

The margin of error is given by this formula:

   (a)

And on this case we have that ME =2 and we are interested in order to find the value of n, if we solve n from equation (a) we got:

  (b)

The critical value for 99% of confidence interval now can be founded using the normal distribution. The significance level is and the critical value would be , replacing into formula (b) we got:

So the answer for this case would be n=30 rounded up to the nearest integer

answer:     true

step-by-step explanation: