To determine the value of the remaining number when we know the average of three numbers and know two of the numbers, follow these steps:
1. Understand the relationship between the average and the sum:
The average of three numbers (let's call them [tex]\(X\)[/tex], [tex]\(Y\)[/tex], and [tex]\(Z\)[/tex]) is given by:
[tex]\[
V = \frac{X + Y + Z}{3}
\][/tex]
2. Express the sum in terms of the average:
To get the sum of the three numbers from the average, rearrange the formula:
[tex]\[
X + Y + Z = 3V
\][/tex]
3. Solve for the remaining number [tex]\(X\)[/tex]:
We need to isolate [tex]\(X\)[/tex] (the unknown number). We already know [tex]\(Y\)[/tex] and [tex]\(Z\)[/tex], so rearrange the equation:
[tex]\[
X = 3V - Y - Z
\][/tex]
Therefore, the remaining number is given by:
[tex]\[
X = 3V - Y - Z
\][/tex]
So the correct choice from the given options is not directly listed, but the closest to this value based on the notation is:
[tex]\[
3V - Y - Z
\][/tex]
Since this exact option is not shown, none of the options A to E is correct.
Given the choices, the intended correct formula should be:
[tex]\[
X = 3V - Y - Z
\][/tex]
