Question
Some states now allow online gambling. As a marketing manager for a casino, you need to determine the percentage of adults in those states who gamble online. How many adults must you survey in order to
confident that your estimate is in error by no more than two percentage points? Complete parts (a) and (b) below.
a. Assume that nothing is known about the percentage of adults who gamble online.
(Round up to the nearest integer)
b. Assume that
of all adults gamble online.
(Round up to the nearest integer)
a. Assume that nothing is known about the percentage of adults who gamble online.
(Round up to the nearest integer)
b. Assume that
(Round up to the nearest integer)
Ask by Bush Stuart. in the United States
Mar 20,2025
Upstudy AI Solution
Tutor-Verified Answer
Answer
To determine the number of adults to survey:
Part (a):
Assuming no prior knowledge, survey 1,692 adults.
Assuming no prior knowledge, survey 1,692 adults.
Part (b):
Assuming that 18% gamble online, survey 998 adults.
Assuming that 18% gamble online, survey 998 adults.
Solution
Given a confidence level of
, the corresponding critical value is approximately
. The margin of error required is
(since two percentage points is 0.02).
We use the sample size formula for a proportion:
Part (a)
Assume nothing is known about the percentage of adults who gamble online. In this case, we use
to maximize the product
.
Substitute the values:
Since
, we have:
Calculate
:
Thus:
Since we round up to the nearest integer:
Part (b)
Assume that
of all adults gamble online, so
(and
).
Substitute the values:
Calculate the product
:
Then, substitute:
Rounding up to the nearest integer gives:
Answered by UpStudy AI and reviewed by a Professional Tutor
Like
error msg


Bonus Knowledge
To determine how many adults you need to survey in order to estimate the percentage of online gamblers with specified confidence, we use the formula for the sample size of a proportion:
where:
-
is the z-value corresponding to your confidence level (for , ), -
is the estimated proportion of the population (unknown in part a, known in part b), -
is the margin of error (in your case, or ).
a. Assuming nothing is known about the percentage of adults who gamble online:
In this case, we can use
(the most conservative estimate):
Calculating that gives:
Rounding up, you need to survey 1692 adults.
b. Assuming
of all adults gamble online:
Here,
:
Calculating that gives:
Rounding up, you need to survey 611 adults.