A psychological test was standardized for a population of tenth-grade students in such a way that...

A psychological test was standardized for a population of tenth-grade students in such a way that the mean must be 500 and the standard deviation must be 100. A sample of 90 twelfth-grade students was selected independently and at random, and each given the test. The sample mean turned out to be 506.7. On this basis, can one say that the population distribution for twelfth grade students would differ from that of tenth-graders?

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Expert Solution

z-Test for one population mean was used to test the claim.

At 0.05 significance level, there is not enough evidence to claim that the population distribution for twelfth grade students would differ from that of tenth-graders.

orchestra answered 1 year ago

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