Question

the mean of 7 variates is 12 if 6 of them are 5,13,9,17,14,10 then find the 7 th observation

Answer 1

We know that mean = Sum of all observations / No. of observations.

Let the seventh observation be x.

Therefore,

5+13+9+17+14+10+x/7 = 12

68 + x = 84

x = 16

There you go!

Answer 2

Given,

The mean of 7 observations = 12

Six observations = 5, 13, 9, 17, 14, and 10

To find,

The value of the 7th observation.

Solution,

The 7th observation will be 16.

We can easily solve this problem by following the given steps.

Now, we know that the formula to find the mean of the given observations is as given below:

Mean = sum of all the observations/total number of observations

In this case, there are a total of 7 observations and the mean is 12.

Now, let's take the 7th observation to be x.

Mean = sum of all the observations/total number of observations

5+13+9+17+14+10+x/7 = 12

68+x/7 = 12

Using the cross multiplication method,

(x+68) = 12×7

(x+68) = 84

x = 84-68

x = 16

Hence, the 7th observation for the given observations is 16.