PSC PROBLEM 70 ANSWER

 3 1/ 6+ 4 1/ 2 -2 2/ 3- 111/ 12

3 1/6 => 19/6 => 38/12

4 1/2 => 9/2 => 54/12

2 2/3 => 8/3 => 32/12

1 11/12 = > 23 /12

>> (38+54-32-23)/12

= 37/12