The average of 45 results is 12. The average of first 22 of them is 15 and that of last 22 is 20. Find the 23 result?  Select:  A) 600  B) 480  C) 750  D) 650  E) 560
23th result = sum of 45results - sum of 44 results   12*45-15*22+20*22 = 540-330+440= 
<gadget id="calculator">540-330+440</gadget>
<output>650</output>
650   Answer is 650
<result>D</result>
The average of 45 results is 12. The average of first 22 of them is 15 and that of last 22 is 20. Find the 23 result?