The average of 11 numbers is 10.8. If the average of first six is 10.5 and that of the last six is 11.4 the sixth number is?  Options:
A) 9.5	B) 12.6	C) 10.5	D) 11.5	E) 12
Explanation:   1 to 11 = 11 * 10.8= 
<gadget id="calculator">11 * 10.8</gadget>
<output>118.8</output>
118.8   1 to 6= 6 * 10.5= 
<gadget id="calculator">6 * 10.5</gadget>
<output>63</output>
63   6 to 11= 6 * 11.4= 
<gadget id="calculator">6 * 11.4</gadget>
<output>68.4</output>
68.4   63 + 68.4= 
<gadget id="calculator">63 + 68.4</gadget>
<output>131.4</output>
131.4 – 118.8= 12.6   6th number = 12.6   Option 12.6
<result>B</result>
The average of 11 numbers is 10.8. If the average of first six is 10.5 and that of the last six is 11.4 the sixth number is?