Question

The mean of 7 observations is 25. The mean of first four observation is 23 and the mean of last four of the missions 29. find the fourth observation.​

Answer 1

Answer:

Fourth term of observation is 33.

Step-by-step explanation:

To find the 4th observation if mean of 7 observations is 25 and the first four observations is 23 and the mean of last four observations is 29

Let the numbers are x1,x2,x3, x4,x5,x6,x7

Mean = Sum of all observation/Total number of observation

x1+x2+x3+x4+x5+x6+x7=25×7

x1+x2+x3+x4+x5+x6+x7=175...eq1

ATQ

x1+x2+x3+x4= 23×4

x1+x2+x3+x4=92...eq2

x4+x5+x6+x7=29×4

x4+x5+x6+x7= 116...eq3

Since eq1=eq2+eq3

but here x4 is added twice,so to find x4

x4=116+92-175

x4=208-175

x4=33

Please mark as Brainliest if it is correct.

Answer 2

Answer:

let the total sum of all observation be x.

x/7=25

x=25*7

x=175

let the sum of first four observation be y.

y/4=23

y=23*4

y=92

let the last four observation be z.

z/4=29

z=29*4

z=116

As the fourth observation is repeating in y and z. Therefore we will subtract x from y+z.

fourth observation= (y+z)-x

=(116+92)-175

=208-175=33