Question

Consider the following set of numbers,


If the average of this set is $12$, then which of the following option is correct?

• A. $x+y=72$
• B. $x-y=23$
• C. $x-y=72$
• D. $x+y=23$

Answer 1

The correct option is D $x+y=23$

The given numbers are $7,9,x,14,19,y$ and their average is $12$.

The formula to calculate the average is

$\text{Average}=\frac{\text{Sum of given numbers}}{\text{Total numbers}}$

Substitute the given values in the formula, to calculate the required result,

$\begin{array}{cc}12& =\frac{7+9+x+14+19+y}{6}\\ 12\times 6& =49+x+y\\ 72& =49+x+y\\ 72-49& =x+y\\ x+y& =23\end{array}$

So, option (d) is correct.