Question

The average of 3 numbers is 6. when one number is removed from the list, the average is 5. which number is removed?

Answer 1

Answer:

8

Step-by-step explanation:

Let the three numbers be x,y, and z

Average=sum of observations÷number of observations

6=x+y+z÷3.

x+y+z=18. eq1

Let number z be removed then

5=x+y÷2

x+y=10. eq2

eq1-eq2

x+y+z-(x+y)=18-10

z=8

Answer 2

The Removed Number is 8

Given:

The average of 3 numbers is 6

when one number is removed from the list, the average is 5

To find:

which number is removed?

Solution:

Given that average of 3 numbers = 6

As we know

Average of 3 numbers = (sum of 3 numbers)/3  

From given data  

sum of 3 numbers/3  = 6

⇒ sum of 3 numbers = 6 × 3 = 18

⇒ Sum of three numbers = 18

After removing 1 number average of 2 numbers = 5

Average of 2 numbers = (sum of 2 numbers)/2  

⇒ (sum of 2 numbers)/2 = 5

⇒ Sum of 2 numbers = 10

The removed number = Sum of three numbers - Sum of 2 numbers

                                     = 18 - 10 = 8  

The Removed Number = 8

#SPJ2