The average of 6 numbers is 6.8.
The average of 6 numbers is 6.8. If one of the numbers is multiplied by a factor of 3, the average of the numbers increases to 9.2. What number is multiplied by 3?
Answer/Solution
7.2
Steps/Work
The average of 6 numbers is 6.8
The sum of 6 numbers will be 6.8 x 6 = 40.8
The average of 6 number after one of the number is multiplied by 3 is 9.2
The sum of the numbers will now be 9.2 x 6 = 55.2
So the sum has increased by 55.2-40.8 = 14.4
Let the number multiplied by 3 be n
Then,
3n = n+14.4
or 2n = 14.4
or n = 7.2
Answer:- C
The sum of 6 numbers will be 6.8 x 6 = 40.8
The average of 6 number after one of the number is multiplied by 3 is 9.2
The sum of the numbers will now be 9.2 x 6 = 55.2
So the sum has increased by 55.2-40.8 = 14.4
Let the number multiplied by 3 be n
Then,
3n = n+14.4
or 2n = 14.4
or n = 7.2
Answer:- C