At the insistence of a government inspector, a new safety device is installed in an assembly-line operation. After the installation of this device, a random sample of 8 days' output gave the following results for numbers of finished components produced:
618 660 638 625 571 598 639 582
Management is concerned about the variability of daily output and views any variance above 500 as undesirable. Test, at the 10% significance level, the null hypothesis that the population variance for daily output does not exceed 500.