Math, asked by risingtudu, 4 months ago

the mean of first 5 observation is 20 and the mean of last 5 observation is 45 what is the mean of all 10 observation ​

Answers

Answered by amitnrw
9

Given : mean of first 5 observation is 20

mean of last 5 observation is 45

To Find  : mean of all 10 observation ​

Solution :

Shortcut

As number of observation is same in both case so we can just find mean of both case

= ( 20 + 45)/2

= 65/2

= 32.5

Detailed :

mean of first 5 observation is 20

=> Sum of first 5 observation is 20 x 5 = 100

mean of last 5 observation is 45

=> Sum of last 5 observation is 4 x5 5 = 225

Sum of 10 observations = 225 + 100 = 325

Total Observations = 10

Mean = 325/10

= 32.5

mean of all 10 observation =  32.5

One liner solution :

( 5 x 20 + 5 x 45) /(5 + 5) = (20 + 45) /2 = 32.5

Learn more:

The average ages in years) of persons in groups A, B and C are ...

brainly.in/question/13429018

the mean of the marks scored by 12 students of a class is 67.4.if the ...

brainly.in/question/12256497

The average daily balance is the mean of the balance in an account ...

brainly.in/question/16094651

Similar questions