The average of 11 numbers is 10.9. If the average of the first six numbers is 10.5 and that of the last six numbers is 11.4, then the middle number is
Choose the correct option: A) 11 B) 11.2 C) 11.4 D) 11.5 E) None
Solution   Middle number	= [(10.5x6+11.4x6) - 10.9x11]   = (131.4 - 119.9)   = 11.5.   Answer 11.5
<result>D</result>
The average of 11 numbers is 10.9. If the average of the first six numbers is 10.5 and that of the last six numbers is 11.4, then the middle number is