Question

Suppose y varies directly as x. If y = 7 when x = 28, what is the value of x when y = 3?

a.
7
b.
9
c.
12
d.
16

Answer 1

Answer: C 12

Explanation:

You set the equation up as y=k.x

So you take what you know in the situation which is y=7 and x=28

So we are still looking for K, so what you do is just divide 28 by 7 and you get 4 which is the answer to this part.

So you keep the 4 and bring to the next side and use 4 to fill in the x variable place

then you just simply do the math 4.3 and get the correct answer 12!

Hope this helps peeps, have a good day!

Answer 2

The answer is C: 12.
It appears that Y will always be 1/4 of X, seeing as Y varies directly with X. When Y is 3, X will be four times that, or 12. :)