A researcher wanted to know if there was a difference in minutes of active play during recess for 2nd-grade girls and 2nd-grade boys. Twenty-three 2nd-grade girls played for a mean of x18.44 minutes and 19 2nd-grade boys played for a mean of x19.15 minutes. The standard error for the difference between the means was x0.73. Treat the girls as Group 1 and the boys as Group 2. Calculate the upper boundary of the 95% confidence interval. Report your answer rounded to the nearest two decimal places.
Added by B P.
Step 1
- Mean for Group 1 (girls), \(\bar{x}_1 = 18.44\) minutes - Mean for Group 2 (boys), \(\bar{x}_2 = 19.15\) minutes - Standard error of the difference between the means, \(SE = 0.73\) Show more…
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