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Find x if the mean of the given data is 11. X 4 9 13 2 31 3

User Heinrich Hartmann
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1 Answer

22 votes
22 votes

Given the data:

X, 4, 9, 13, 2, 31, 3

Mean of data = 11

Let's find the value of X.

To find the mean of a data set, divide the sum of the values by the number of values in the set.

Apply the formula:


\text{mean=}\frac{\text{ sum of data}}{nu\text{mber of values}}

Where:

number of values = 7

mean = 11

sum of data = X + 4 + 9 + 13 + 2 + 31 + 3

Thus, we have:


\begin{gathered} 11=(X+4+9+13+2+31+3)/(7) \\ \\ 11=(X+62)/(7) \end{gathered}

Let's solve for x in the equation above.

Multiply both sides of the equation by 7 to eliminate the denominator:


\begin{gathered} 11\ast7=(X+62)/(7)\ast7 \\ \\ 77=X+62 \end{gathered}

Subtract 62 from both sides of the equation:


\begin{gathered} 77-62=X+62-62 \\ \\ 15=X \\ \\ X=15 \end{gathered}

Therefore, the value of X is 15.

ANSWER:

15

User Hgascon
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