Yvaries inversely with x k=2.8 what is the value of x when y is 22.4

Alawn mower manufacturer incurs a total of 34,816 in overhead costs and 388 per lawn mower in production costs. how many lawn mowers were manufactured if the average cost of productions is 660

True or false look at the picture pls : /

Which of the choices shown could be used to prove that aacp=abcp ?