Look at the results of different experiments, and determine if they are statistically significant.


Keita has a juice stand. He made a new sign that he thinks will attract more customers than the current sign.
He randomized 60 workdays between a treatment group and a control group. On each day from the treatment group he put up the new sign, and on each day from the control group he put up the old sign.
The results of the experiment showed that the mean number of bottles sold under the new sign is 12 more than the mean number of bottles sold under the old sign. To test whether the results could be explained by random chance, Keita created the table below, which summarizes the results of 1000 re-randomizations of the data (with differences between means rounded to the nearest 2 bottles).
According to the simulations, what is the probability of the treatment group's mean being higher than the control group's mean by 12 bottles or more?
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0, point, 75
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • a percent, like 12, point, 34, percent
Assume that if the probability you found is lower than 5, percent, then the result should be considered as significant.
What should we conclude regarding the experiment's result?
Please choose from one of the following options.
Treatment group mean minus Control group meanFrequency
minus, 147
minus, 1218
minus, 1020
minus, 846
minus, 697
minus, 4103
minus, 2123