Question

$x\propto y\text{and x}\propto \frac{1}{z}.$ if y = 5, z = 4 , then x = 3. Now, if y = 30 and z = 16 ,then x =

• A. 2
• B. 9
• C. 9/2
• D. 5/2

Answer 1

The correct option is C

9/2

$x\propto y\text{and x}\propto \frac{1}{z}$

$\Rightarrow x\propto \frac{y}{z}$

$\Rightarrow x=k.\left(\frac{y}{z}\right)$

Putting the given values of x, y and z we get :

$3=k.\left(\frac{5}{4}\right)$

$\Rightarrow k=\frac{12}{5}$

Now , putting the new value of k along with y and z we get :

$x=\left(\frac{12}{5}\right)\times \left(\frac{30}{16}\right)=\frac{9}{2}$