g The manager of a grocery store has taken a random sample of 100 customers. The average length of time it took the customers in the sample to check out was 3.1 minutes with a standard deviation of 0.5 minutes. We want to test to determine whether or not the mean waiting time of all customers is significantly more than 3 minutes. The p-value is

Step-by-step explanation:

Null hypothesis: u <= 3 minutes

Alternative hypothesis: u > 3minutes

Using a z test formula, z score is

z = (x - u) / (s/√n)

Where x = 3.1, u = 3, s = 0.5, n = 100

z = (3.1 - 3) / (0.5/√100)

z = (0.1) / (0.5/10)

z = 0.1/0.05

z = 2

To calculate for the p value assuming a 0.05 level of significance, the p value is 0.02275 which is less than 0.05. Thus we will reject the null and conclude that there is enough statistics evidence to show that the mean waiting time of all customers is significantly more than 3 minutes.

answer:

payment just for service  

→

$

87.12

payment for service including tax

→

$

94.09

explanation:

service only with 20% tip  

→

$

72.6

(

1

+

20

100

)

=

$

87.12

in the opening of the question the word 'service' is associated only with the pretax value.

the closing part of the question asks: how much did she pay for the  

service

−−−−−−  

so technically the answer is  

→

$

72.6

(

1

+

20

100

)

=

$

87.12

however, the intention of the question provider may have been that your answer is to be  

$

87.12

(

1

+

8

100

)

=

$

94.09

to 2 decimal places.

'

payment just for service  

→

$

87.12

payment for service including tax

→

$

94.09

tony b

mar 21, 2017

answer:

trying to explain it another way

explanation:

service charge  

.

→

$

72.60

20% tip  

20

100

×

$

72.60

=

$

14.52

−−−−−−  

←

add

$

87.12

tax  

8

100

×

$

87.12

=

$

6.97

−−−−−  

←

add

$

94.09

related questions

step-by-step explanation: