Two cellular network companies, Alpha and Omega, advertise that their data network is the fastest for a certain region. Members from a consumer advocacy group tested the network speed for both companies. The members tested the network download speed hundreds of times throughout the region. The sample mean of the download speed for Alpha is 56.8 megabits per second (Mbps) and is 57.2 Mbps for Omega.
To test whether the results could be explained by random chance, the members of the group simulated 1,000 rerandomizations of the data for the difference found by subtracting the mean download speed for Alpha from the mean download speed for Omega. The table shows the results of the differences.
Difference Frequency
Less than −0.4 6
Greater than or equal to −0.4 and less than −0.2 27
Greater than or equal to −0.2 and less than 0 246
Greater than or equal to 0 and less than 0.2 408
Greater than or equal to 0.2 and less than 0.4 278
Greater than or equal to 0.4 35
Explain whether the difference in the download speeds between the two networks is significant.
A) The differences in download speed are not significant because the average download speed for Alpha being at least 0.4 Mbps greater than for Omega only occurs in 0.6% of the samples.
B) The differences in download speed are not significant because the average download speed for Omega being at least 0.2 Mbps greater than for Alpha only occurs in 31.3% of the samples.
C) The differences in download speed are significant because the average download speed for Omega being at least 0.4 Mbps greater than for Alpha only occurs in 3.5% of the samples.
D)The differences in download speed are significant because the average download speed for Alpha being at least 0.2 Mbps greater than for Omega only occurs in 3.3% of the samples.