Two types of phone operating system are being tested to determine

if there is a difference in the proportions of system failures (crashes). Fifteen out of a random sample of 150 phones with OS1had system failures within the first eight hours of operation. Nine out of another random sample of 150 phones with OS2had system failures within the first eight hours of operation. OS2is believed to be more stable (have fewer crashes) than OS1.

What can you conclude about the two operating systems?

Short Answer

Expert verified

There is insufficient evidence to reject the null hypothesis at the 5 percent level of significance, thus the data do not reveal that OS2has fewer system failures thanOS1.

Step by step solution

01

Given information  

Phone operating systemsOS1andOS2.

02

Conclusion about the two operating systems 

The level of significance is at 5% that is α=0.05.

The output of the previous exercise 10.49 is :

If α<pis a positive number, the null hypothesis is not rejected.

There is insufficient evidence to reject the null hypothesis at the 5%level of significance, thus the data do not reveal that OS2has fewer system failures than localid="1652985249407" OS1.

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