SOLUTION: The average of 6 numbers is 20. When another number is added and included in the average, the average of the 7 numbers is 23. Find the value of the seventh number. Thank you!

Algebra ->  Average -> SOLUTION: The average of 6 numbers is 20. When another number is added and included in the average, the average of the 7 numbers is 23. Find the value of the seventh number. Thank you!      Log On


   

Question 947070: The average of 6 numbers is 20. When another number is added and included in the average, the average of the 7 numbers is 23. Find the value of the seventh number. Thank you!
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
the average of 6 numbers is 20.
this means the total of the 6 number is 6 * 20 = 120.

you add another number.
the average of the 7 numbers is 23.
the total of the 7 numbers is 7 * 23 = 161.

the difference between 161 and 120 is equal to 41.

the 7th number has to be equal to 41.

120 + 41 = 161 / 7 = 23.