Question

The mean of 7 number 7,9,12,x,5,4,11 is 9. The missing number x is *

Answer 1

Answer:

Mean = Sum of observations / Number of observations.

Here,

Number of observations = 7

Given, Mean = 9

So,

7+9+12+x+5+4+11. / 7. = 9

48 +x / 7 = 9

48 +x = 7×9

48 + x = 63

x = 63 - 48

x = 15

Hope this helps you....

Mark me as brainliest.....

Answer 2

Answer below:

The other number is 15.

Explanation:

Number of observations = 7

Mean = 9

So, sum of the numbers =  7*9 = 63

Sum of the numbers other than x = 7+9+12+5+4+11

                                                          = 48

So, the other number = 63-48

                                      = 15

Hope it helps......

Mark my answer as the brainliest.