8 and 7 are both a factor of 56.
Given parameters:
y varies directly as w;
This interpreted implies that as y increases, we increases by a certain factor or amount;
So, y ∝ w
y = kw
where k is the constant of proportionality
Now, given that y = 8 and w = 2
Input in the equation to solve for k;
8 = k x 2
Solving k gives, k = 4
Now to the second part,
if v is directly proportional to w;
v = k w
So v = 4w
The equation that relates v to w is v = 4w
There will be excactly 400 fiction books. The ratio of fiction to all is 4 to 9, or 4 to 900.
