Children 15723

There were children in the camp. 2/3 of the children went on a trip, 1/7 went swimming, and X went to the gym. How many children were in the camp?

Result

n : (Correct answer is: )

Step-by-step explanation:

$$\begin{gathered} n=\frac{2}{3}n+\frac{1}{7}n+X \\ n(1-\frac{2}{3}+\frac{1}{7})=X \\ n\cdot \frac{10}{21}=X \\ n=n=X\cdot \frac{21}{10} \end{gathered}$$

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