Males use the Internet 1017 hours per week standard deviatio
Solution
Let u1 = mean of males
 u2 = mean of females
Formulating the null and alternative hypotheses,              
               
 Ho:   u1 - u2   <=   0  
 Ha:   u1 - u2   >   0  
 At level of significance =    0.05          
 As we can see, this is a    right   tailed test.      
 Calculating the means of each group,              
               
 X1 =    10.17          
 X2 =    9.08          
               
 Calculating the standard deviations of each group,              
               
 s1 =    11.71          
 s2 =    12.26          
               
 Thus, the standard error of their difference is, by using sD = sqrt(s1^2/n1 + s2^2/n2):              
               
 n1 = sample size of group 1 =    118          
 n2 = sample size of group 2 =    157          
Thus, df = n1 + n2 - 2 = 273
Also, sD =    1.45583031          
               
 Thus, the t statistic will be              
               
 t = [X1 - X2 - uD]/sD =    0.748713633          
               
 where uD = hypothesized difference =    0          
               
 Now, the critical value for t is              
               
 tcrit =        1.650454303      
               
 As |t| < 1.6504, we FAIL TO REJECT THE NULL HYPOTHESIS.          
           
 Thus, there is no significant evidence that men use the Internet more hours than women. [CONCLUSION]

