Question

If x varies y directly as y and when x = 7 when y = 28 , find x when y = 9

Answer 1

Answer:

x=2.25 according to the question

Answer 2

Answer:

The answer is $\frac{9}{4}$

Step-by-step explanation:

Given x varies directly as y

$\Rightarrow x=ky$, where k is some constant

Given when $x=7$ then $y=28$

Substitute them in above result

$\Rightarrow 7=k(28)\Rightarrow k=\frac{7}{28}=\frac{1}{4}$

Now when $y=9$

    $x=ky=\frac{1}{4}(9)=\frac{9}{4}$