A company selling widgets has found that the number of items sold, x, depends upon the price, p at which they're sold, according the equation $\displaystyle {x}=\frac{{80000}}{{\left({0.5}{p}+{1}\right)}^{{2}}}$

Due to inflation and increasing health benefit costs, the company has been increasing the price by $0.05 per month. Find the rate at which revenue is changing when the company is selling widgets at $6 each.

Revenue is decreasing by Preview Question 6   dollars per month

Hint: Give your answer as a positive value.