The average of 5 numbers is 6.8. If one of the numbers is multiplied by a factor of 3, the average of the numbers increases to 12.8. What number is multiplied by 3?
Pick one:
A) 15.0  B) 13.0  C) 13.9  D) 10.0  E) 6.0
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 3 is 12.8   The sum of the numbers will now be 12.8 x 5 = 64   So the sum has increased by  64-34= 
<gadget id="calculator"> 64-34</gadget>
<output>30</output>
30   Let the number multiplied by 3 be n   Then,   3n= n+30   or 2n = 30   or n = 15   15.0nswer:- 15.0
<result>A</result>
The average of 5 numbers is 6.8. If one of the numbers is multiplied by a factor of 3, the average of the numbers increases to 12.8. What number is multiplied by 3?