Question

x	2	a	b	3	8	6
y	36	4	9	24	c	d
z	e	f	6	16	g	8

$x,y,z$ are proportional to each other. What is the proportionality between $y$ and $z$?

• A. Direct
• B. Inverse
• C. Both
• D. None

Answer 1

The correct option is A Direct

$xy=2\times 36=3\times 24=72=k_1\Rightarrow x\propto \frac{1}{y}$

$xz=3\times 16=6\times 8=48=k_2\Rightarrow x\propto \frac{1}{z}$

$xy=k_1,xz=k_2$

$\Rightarrow \frac{xy}{xz}=\frac{k_1}{k_2}$

$\Rightarrow \frac{y}{z}=\frac{k_1}{k_2}=k_3$

$\Rightarrow y\propto z$

$y$ is directly proportional to $z$.