For every pound shipped, $0.40 is charged. This can be represented by the mathematical equation: y=0.4x, where x is the pounds to ship and y is the total cost. If we plug in 20 as x to find what the total cost would be, we would have the equation, y=0.4*20, and y would equal 8, meaning that the total cost is $8.00.
In 5 years, the price increased about 30%. I am not good at perentages, so correct me if I'm wrong. Also this is an estimation, not the exact percentage.
