The average of 5 numbers is 6.8. If one of the numbers is multiplied by a factor of 2, the average of the numbers increases to 9.2. What number is multiplied by 2?
Choose one:
A) 12.0  B) 30.0  C) 30.9  D) 40.0  E) 60.0

Rationale: the average of 5 numbers is 6.8 the sum of 5 numbers will be 6.8 x 5 = 34 the average of 5 number after one of the number is multiplied by 2 is 9.2 the sum of the numbers will now be 9.2 x 5 = 46 so the sum has increased by 46 - 34 = 12 let the number multiplied by 2 be n then , 2 n = n + 12 or n = 12 answer : - a
Answer: A