The average of 6 no.'s is 6.40. The average of 2 of them is 6.2, while the average of the other 2 is 6.1. What is the average of the remaining 2 no's?
Choose the correct answer:
A) 2.3  B) 2.6  C) 6.9  D) 4.5  E) 4.6

Rationale: "sum of the remaining two numbers = ( 6.4 * 6 ) - [ ( 6.2 * 2 ) + ( 6.1 * 2 ) ] = 38.40 - ( 12.4 + 12.2 ) = 38.40 - 24.6 = 13.80 required average = ( 13.8 / 2 ) = 6.9 answer : c"
Answer: C