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Lesley E. Tan investigated the relationship between left-handedness vs. right-handedness and motor competence in preschool children. Random samples of 41left-handed preschool children and 41right-handed preschool children were given several tests of motor skills to determine if there is evidence of a difference between the children based on this experiment. The experiment produced the means and standard deviations shown in Table 10.36. Determine the appropriate test and best distribution to use for that test.

Left-handedRight-handedSample size4141Sample mean97.598.1Sample standard deviation17.519.2

a. Two independent means, normal distribution

b. Two independent means, Student’s-t distribution

c. Matched or paired samples, Student’s-t distribution

d. Two population proportions, normal distribution

Short Answer

Expert verified

The provided data is two independent means, Student’s-t distribution.

Step by step solution

01

Given Information

Given data:

Left-handedRight-handedSample size4141Sample mean97.598.1Sample standard deviation17.519.2

02

Explanation

Testing can be carried out if the data and mean-variance of both samples are determined, and the population standard deviation is unknown, two independent means, Student's-t distribution.

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