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Question
Explain the concept of direct variation.
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Solution
\[\text{ When two variables are connected to each other in such a way that if we increase the value of one variable, the value of other variable also increases } \]
\[\text{ and vice - versa . Similarly, if we decrease the value of one variable, the value of other variable also decreases and vice - versa .} \]
\[\text{ Therefore, if the ratio between two variables remains constant, it is said to be in direct variation } .\]
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