Question

six numbers have an average of 38. A number is removed and the average becomes 40. What number was removed?

Answer 1

Answer:

28

Step-by-step explanation:

Let's assume that each of the 5 left over numbers are 'a' , and the removed number is 'b'.

So, (a + b)/6=38

After b is removed, a/5=40

So we get a = 40*5 = 200

Which means, the sum of the remaining 5 numbers are 200

Now, replacing the value of a in the 1st equation, we get :

=> (200+b)/6=38

=> 200+b = 38*6 = 228

=> b = 228 - 200 = 28

Therefore , the removed number is 28.

Hope you understood my explanation. If yes, then plz don't forget to mark my answer as the Brainliest :)

Answer 2

Step-by-step explanation:

Given :-

Six numbers have an average of 38. A number is removed and the average becomes 40.

To find :-

What number was removed?

Solution :-

Given that

Average of 6 numbers = 38

We know that

Average = Sum of all observations/Number of all observations

=> 38 = Sum of 6 numbers/6

=> Sum of 6 numbers = 38×6

=> Sum of 6 numbers = 228 -----------(1)

If one number is removed then the remaining numbers = 6-1 = 5

Average of 5 numbers = 40

=> 40 = Sum of 5 numbers / 5

=> Sum of 5 numbers = 40×5

=> Sum of 5 numbers = 200 -------(2)

Removed number =

Sum of 6 numbers - Sum of 5 numbers

=> 228-200

=> 28

The number = 28

Answer:-

Removed number for the given problem is 28

Used formulae:-

Average = Sum of all observations/Number of all observations