Question

A survey commissioned by a health care group reported that 21% of New Zealanders consume five or more servings of soft drinks per week. The data were obtained by an online survey of 2,009 randomly selected New Zealanders over 15 years of age.

(a) What number of survey respondents reported that they consume five or more servings of soft drinks per week? (Round your answer to the nearest whole number.)
422

(b) Find a 95% confidence interval for the proportion of New Zealanders who report that they consume five or more servings of soft drinks per week.

19.22%, 22.78%

(c)  Discuss reasons why the estimate might be biased. (Select all that apply.)

The survey respondents might have lied.

The survey questions may have been biased.

The survey was commissioned by a health care group.

The survey did not include people under 15 years of age.

The survey only included New Zealanders.

The survey had 2,009 people.

Answer 1

= 0.21

n= 2009

a) number of survey respondents reported that they consume five or more servings of soft drinks per week

= 0.21 * 2009 =421.89 = 422

b) 95% Confidence Interval for p

=[ ]

= [ ]

= [ )

= (0.1922 , 0.2278)

= 19.22%, 22.78%

c) Reasons why the survey may be biased-

-The survey was commissioned by a health care group.

-The survey did not include people under 15 years of age.