The average of 11 numbers is 10.9. If the average of first six is 10.5 and that of the last six is 11.4
the sixth number is?
A.11.0
B.11.3
C.11.4
D.11.5
Answer and Feedback
Answer:D
Feedback:1 to 11 = 11 * 10.9 = 119.9
1 to 6 = 6 * 10.5 = 63
6 to 11 = 6 * 11.4 = 68.4
63 + 68.4 = 131.4 – 119.9 = 11.5
6th number = 11.5
1 to 6 = 6 * 10.5 = 63
6 to 11 = 6 * 11.4 = 68.4
63 + 68.4 = 131.4 – 119.9 = 11.5
6th number = 11.5