Question

The average of three numbers is XYZ. If the sum of two numbers is X+Y, what is the other number?

Answer 1

Step-by-step explanation:

Given :-

The average of three numbers is XYZ. and the sum of two numbers is X+Y.

To find :-

What is the other number ?

Solution :-

Given that :

The average of three numbers = XYZ

We know that

Average = Sum of all observations/Number of all observations

=> XYZ = Sum of the three numbers / 3

=> Sum of the three numbers = 3 XYZ

Given that

Sum of the two numbers = X+Y

Now,

The other number = Sum of the three numbers - Sum of the two numbers

=> 3XYZ - (X+Y)

=> 3XYZ - X - Y

Answer:-

The other number is 3XYZ-(X+Y) (or) 3XYZ-X-Y

Used formulae :-

Average = Sum of all observations/Number of all observations

• Average is also known as Mean , Arithmetic Mean .