Question

Monthly rent paid by undergraduates and graduate students.

Undergraduate Student Rents (n = 10)
800	750	840	710	710
780	750	620	990	660

Graduate Student Rents (n = 12)
1,120	890	900	880	740	860
740	780	960	880	880	860

(a) Construct a 98 percent confidence interval for the difference of mean monthly rent paid by undergraduates and graduate students, using the assumption of unequal variances with Welch's formula for d.f. (Do not round the intermediate calculations. Round your final answers to 3 decimal places. Negative values should be indicated by a minus sign.)
  
The 98% confidence interval is from  to

(b) What do you conclude?
  

• We can conclude there is a significant difference in means for undergraduate and graduate rent.

• We cannot conclude there is a significant difference in means for undergraduate and graduate rent.

Answer 1

The statistical software output for this problem is:

Two sample T confidence interval: Hi : Mean of Sample 1 12 : Mean of Sample 2 H1 - H2 : Difference between two means (without pooled variances) 98% confidence interval results: Difference Sample Diff. Std. Err. DF L. Limit U. Limit P1 - H2 -113.16667 43.954493 19.183702 -224.69118 -1.6421535

Hence,

a) 98% confidence interval:

From -224.691 to -1.642

b) We can conclude there is a significant difference in means for undergraduate and graduate rent. Option A is correct.