According to the standards of the battery of tests measuring various aptitudes of employees assigned to manual tasks, the national average (m) for the test allowing the visual-motor coordination of an individual to be assessed is 90 with a deviation of type(s) of 15. The results are also considered to be normally distributed. A group of 69 individuals from a processing plant in the Estrie region obtained an average of 86.4 for this test. Assuming that this group is a representative sample of the population of employees assigned to manual tasks, can we say at the significance level of 0.05 that it corresponds to the national average?

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