Question 3435
The average of three numbers is the sum of the numbers divided by 3. Let the numbers be X, Y and Z, then<br>
{{{(X + Y + Z)/3 = V}}}.<br>
multiply both sides by 3 to get {{{X + Y + Z = 3V}}}.<br>
subtract Y and Z from both sides to get {{{X = 3V - Y - Z}}}<br>
The remaining number X is 3V- Y - Z