Two speed studies are taken under situations that are considered identical and the following results were obtained: • study 1, mean is 30.8, standard deviation is 6.2, and the sample size is 100 • study 2, mean is 32.2, standard deviation is 5.4, and the sample size is 200 are the means in the two studies significantly different at the 95% confidence level?

No,  the means in the two studies significantly is not different at the 95% confidence level.

Step-by-step explanation:

Since we have given that

Study 1,

Mean = 30.8,

Standard Deviation = 6.2,

Sample size = 100

And

Study 2

Mean = 32.2,

Standard Deviation = 5.4,

Sample size = 200

So, Hypothesis would be

So, At 95% confidence level, z = 1.96

So, the test statistic value would be

Since 1.96>-1.9228

So, we will accept the null hypothesis.

Hence,No,  the means in the two studies significantly is not different at the 95% confidence level.

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