Mark (✓) against the correct answer:
Question:

Mark (✓) against the correct answer:

x and y vary directly. When x = 3, then y = 36. What will be the value of x when y = 96?

(a) 18

(b) 12

(c) 8

(d) 4

Solution:

(c) 8

$x$ and $y$ var $y$ directly.

Then $x=k y$, where $k$ is the constant of proportionality.

$\Rightarrow k=\frac{x}{y}$

Now, $\frac{3}{36}=\frac{x_{1}}{96}$

$\Rightarrow \frac{96 \times 3}{36}=x_{1}$

$\Rightarrow 8=x_{1}$

$\therefore$ Value of $x=8$