Family members

Three years ago, the average age of a family of five members was 27. The present average age is also 27 after a child is included in the family. Find the age of the child.

Final Answer:

x =  12

Step-by-step explanation:

$$\begin{gathered} 27=\frac{5\cdot (27+3)+x}{5+1} \\ 27\cdot 6=5\cdot (27+3)+x \\ x=12 \end{gathered}$$

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