Question

If the arithmetic mean of the two numbers X1 and X2 is 5 if X1=3, then X2 is:

Answer 1

Answer:

X1 + X2 = 5 (given)

2

x1 + x2 = 5×2

3 + x2 = 10 (substitute the value of x1 = 3)

x2 = 10 - 3

x2 = 7

Answer 2

Given:

The arithmetic mean of the two numbers $X_1$ and $X_2$  is 5

If $X_1$ = 3

To find:

The value of $X_2$

Solution:

The arithmetic mean of the two numbers $X_1$ and $X_2$  is 5

The arithmetic mean is the sum of the numbers divided by the number of terms.

The arithmetic mean of two numbers is given as,

$\frac{X_1+X_2}{2}$ = 5

Substitute $X_1$ = 3

$\frac{3+X_2}{2}$ = 5

3 + $X_2$  = 5 × 2

3 + $X_2$  = 10

$X_2$ = 10 - 3

$X_2$ = 7

The other number $X_2$ is 7

Final answer:

The value of $X_2$ is 7