The average of 5 numbers is 7.4. 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?
Pick
A) 1.5  B) 3.0  C) 3.9  D) 4.5  E) 6.0
The average of 5 numbers is 7.4   The sum of 5 numbers will be 7.4 x 5 = 37   The average of 5 number after one of the number is multiplied by 3 is 9.2   The sum of the numbers will now be 9.2 x 5 = 46   So the sum has increased by  46-37= 
<gadget id="calculator"> 46-37</gadget>
<output>9</output>
9   Let the number multiplied by 3 be n   Then,   3n= n+9   or 2n = 9   or n = 4.5   Answer:- 4.5
<result>D</result>
The average of 5 numbers is 7.4. 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?