Question

y varies directly with x. y is 24 when x is 16. what is x when y is 30? x = ?

Explanation:

Step1: Find the constant of variation

Since $y$ varies directly with $x$, the equation is $y = kx$. When $y = 24$ and $x = 16$, we find $k$ by substituting these values into the equation: $k=\frac{y}{x}=\frac{24}{16}=\frac{3}{2}$.

Step2: Find $x$ when $y = 30$

Substitute $y = 30$ and $k=\frac{3}{2}$ into $y = kx$. We get $30=\frac{3}{2}x$. Solving for $x$, we multiply both sides by $\frac{2}{3}$: $x = 30\times\frac{2}{3}=20$.

Answer:

$20$