A computer system administrator notices that computers running a particular operating system seem to freeze up more often as the installation of the operating system ages. She measures the time (in minutes) before freeze-up for 7 computers one month after installation, and for 9 computers seven months after installation. The results are as follows.

Can you conclude that the time to freeze-up is more variable in the seventh month than in the first month after installation? Use the α = 0.01 level of significance.

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One month: Seven months: 207.4 233.1 215.9 235.1 225.6 244.4 245.3 84.3 53.2 127.3 201.3 174.2 246.2 149.4 156.4 103.3