A student took 6 courses last year and received an average (arithmetic mean) grade of 100 points. The year before, the student took 5 courses and received an average grade of 60 points. To the nearest tenth of a point, what was the student’s average grade for the entire two-year period? Pick one
A) 79	B) 89	C) 95	D) 81.81	E) 97.2
Let the 6 courses that were taken last year be A1 , A2, A3 , A4 , A5 , A6   A1+A2+A3+A4+A5+A6 = 100*6= 
<gadget id="calculator">100*6</gadget>
<output>600</output>
600   The year before , the 5 courses be B1, B2 , B3 , B4 , B5   B1+B2+B3+B4+B5= 60*5= 
<gadget id="calculator">60*5</gadget>
<output>300</output>
300   Student's average= (600+300)/11 = 81.81   Answer 81.81
<result>D</result>
A student took 6 courses last year and received an average (arithmetic mean) grade of 100 points. The year before, the student took 5 courses and received an average grade of 60 points. To the nearest tenth of a point, what was the student’s average grade for the entire two-year period?