Sam Gates, Marketing Director of Mansfield Motors' Electrical Division, is leading a study to assess the relative importance of product features. An item on a survey questionnaire distributed to 100 Mansfield customers asked them to rate the importance of 'efficiency of operation' on a scale of 1 to 10 (with 1 meaning 'not important' and 10 meaning 'highly important'). His staff assembled the following statistics.

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