Question

The mean of 5 numbers if 10. If one more number is included the mean of all the six numbers becomes 9. Find the value of the included number.​

Answer 1

Answer:

The value of included number is 4.

Step-by-step explanation:

Since we have given that

Number of observations = 5

Mean = 10

So, it becomes,

\begin{gathered}\dfrac{\sum x}{5}=10\\\\\sum x =50\end{gathered}

5

∑x

=10

∑x=50

If one number is included , the new mean = 9

So, it becomes,

\begin{gathered}\dfrac{\sum x+new}{6}=9\\\\\sum x+new=54\\\\50+new=54\\\\new=54-50\\\\new=4\end{gathered}

6

∑x+new

=9

∑x+new=54

50+new=54

new=54−50

new=4

Hence, the value of included number is 4.

# learn more:

The mean of 10 numbers is 12.5 and the mean of first 6 numbers is 15 and the mean of last 5 number is 10 .find the sixth number

https://brainly.in/question/3607153

Answer 2

Answer:

4

Step-by-step explanation:

Let the number be x

The mean of 5 numbers = 10

The sum of 5 numbers = 10×5=50

Then,

50+x = 9

6

50+x = 9×6

x = 54-50

x = 4

Hence the included number is 4.