Question

Response Question

How much do Americans pay for coffee on average? In a 2015 survey of 105 randomly selected U.S.
adults, the respondents were asked what price they paid for their most recent purchase of coffee.
The sample data had a mean of $3.42 and a standard deviation of $0.75.

Answer 1

The right solution is "3.29, 3.57".

Explanation:

Seems that the given problem is incomplete. Below is the attachment of the complete and appropriate query.

The given values are:

Randomly selected adults,

`n = 105`

Mean,

`\bar{x} = 3.42`

Standard deviation,

`s = 0.75`

Now,

At 95% confidence level if given by,

=
`\bar{x} \ \pm \ Z_{(\alpha)/(2) }* (s)/(√(n) )`

On putting the given values, we get

=
`3.42 \ \pm \ Z_{(0.05)/(2) }* (0.75)/(√(105) )`

=
`3.42 \ \pm \ 1.96* 0.073`

=
`3.42 \ \pm \ 0.143`

=
`3.29, 3.57`