Question

answer me please fast​

Answer 1

Answer:

14.66

Step-by-step explanation:

Given---> Mean of the observations , x , x+3 , x+5, x+7, x+10 is 9.

To find---> Mean of last three observations.

Solution---> We know that

Mean = Sum of all observations / number of observation

ATQ, mean of x , ( x + 3 ) , ( x + 5 ) ,

( x +7 ) , ( x + 10 ) is 9

Mean = x+(x+3)+(x+5)+(x+7)+(x+10) / 5

=> 9 = (x+x+x+x+x) + (3+5+7+10) / 5

=> 9 = ( 5x + 25 ) / 5

=> 9 × 5 = 5x + 25

=> 45 = 5x + 25

=> 45 - 25 = 5x

=> 20 = 5x

=> x = 20 / 5

=> x = 4

Now we find the mean of last three observations

Mean of last three observations

= ( x + 5 ) + ( x + 7 ) + ( x + 10 ) / 3

= ( x + x + x ) + ( 5 + 7 + 10 ) / 3

= 3x + 22 / 3

Putting x = 4 in it , we get,

= 3 ( 4 ) + 22 / 3

= ( 12 + 22 ) / 3

= 44 / 3 = 14.66

#Answerwithquality

#BAL