

Question
========

The waiting time (in minutes) at the cashier of two supermarket
chains with different cashier systems is compared. The following
statistical test was performed:


```

	Two Sample t-test

data:  Waiting by Supermarket
t = 4.1777, df = 108, p-value = 2.996e-05
alternative hypothesis: true difference in means between group Sparag and group Consumo is greater than 0
95 percent confidence interval:
 1.241878      Inf
sample estimates:
 mean in group Sparag mean in group Consumo 
             5.419987              3.360063 
```

Which of the following statements are correct? (Significance level 5%)

Answerlist
----------
* The absolute value of the test statistic is larger than 1.96.
* A one-sided alternative was tested.
* The p-value is larger than 0.05.
* The test shows that the waiting time is longer at Sparag  than at Consumo.
* The test shows that the waiting time is shorter at Sparag than at Consumo.

Solution
========

Answerlist
----------
* True. The absolute value of the test statistic is equal to 4.178.
* True. The test aims at showing that the difference of means is  larger than 0.
* False. The p-value is equal to 3e-05.
* True. The test result is significant ($p < 0.05$) and hence the alternative is shown that the difference of means is larger than 0.
* False. The test aims at showing that the waiting time at Sparag is longer than at Consumo. 

Meta-information
================
extype: mchoice
exsolution: 11010
exname: 2-sample t-test
