Need Step by Step Solutions for all the problems:

STAT 200

Chapter 9 Practice Problems

Question 1) One group of 30 normally developing toddlers earned a mean score of 50 for aggression on the CBCL (SD = 8). A group of 27 aggressive toddlers earned a mean score of 57 for this measure (SD = 3). Is the difference between these two groups statistically significant?

Question 2) One group of 15 normally developing infants earned a mean score of 3() for mental development on the Bayley Scales of Infant Development (SD = 7). A group of 10 developmentally delayed infants earned a mean score of 25 for this measure (SD = 5). Is the difference between these two groups statistically significant?

Question 3) One group of 40 Statistics students earned a mean score of 90 for an exam score (SD = 11). A group of 33 Statistics students earned a mean score of 87 for this measure (SD = 3). Is the difference between these two groups statistically significant?

Question 4) One group of 21 normally developing children earned a mean score of 50 for depression on the CBCL (SD = 13). A group of 39 depressed children earned a mean score of 55 for this measure (SD = 7). Is the difference between these two groups statistically significant?

Question 5) One group of 55 normally developing toddlers earned a mean score of 70 for social skills on the CBCL (SD = 8). A group of 47 developmentally delayed toddlers earned a mean score of 66 for this measure (SD = 2). Is the difference between these two groups statistically significant?