In: Math
Watch Corporation of Switzerland claims that its watches on average will neither gain nor lose time during a week. A sample of 18 watches provided the following gains (+) or losses (−) in seconds per week.
−0.43 | −0.22 | −0.42 | −0.37 | +0.27 | −0.23 | +0.32 | +0.54 | −0.19 |
−0.29 | −0.34 | −0.55 | −0.44 | −0.56 | −0.05 | −0.19 | −0.24 | +0.08 |