Question

Suppose that y varies directly with x and y=3 when x=9 what is y when x=18

Answer 1

Given,

The value of y is 3 when the value of x is 9.

x is directly proportional to y.

The value of x is 18.

The value of y is,

$\begin{gathered} \frac{3}{y}=\frac{9}{18} \\ 9\times y=3\times18 \\ y=\frac{54}{9} \\ y=6 \end{gathered}$

Hence, the value of y is 6.