Question

what number must be added to the sequence 7, 13, and 10 to get an average of 13?

Answer 1

Answer:

22

Step-by-step explanation:

Let the no. be x

(7+13+10+x)/4 =13

30 + x = 4 x 13 =52

x=52-30

x = 22

Answer 2

The number would be 22.

Step-by-step explanation:

Given: Three numbers 7, 13, and 10

To be found: A fourth number, such that the average of all the four becomes 13.

Formula to be used: Average =  Sum of observations/ Number of Observations

Solution:

• Let the fourth number be 'x'

Then,

• Sum of all observations $= 7+13+10+x$

• Number of observations $= 4$

Therefore, Average $= 13 = \frac{7+13+20+x}{4}$

$13 = \frac{7+13+10+x}{4}$

$13 = \frac{30+x}{4}$

$13\times 4 = 30+x$

$52 = 30+x$

$x = 52-30$

$x =22$

• Hence, the fourth number would be 22.