The first statement "<span>y varies directly as x" means that as y increases, x also increases. To help us we need to assign a proportionality constant, k. We can now say:</span> y=kx where k is just a constant. Then substitute the values,
180=kn n=5k
With these equation we know that k is equal to (positive or negative) 6 and therefore we can get n to be (positive or negative) 30.