I think you times all of the inchs together. 5x3x2=30.
I dont know if i am right tho. Hope this help ya.
80%, 1000-200 = 800/1000 or 80%
There is the formula now just plug in the values and you will get your answer.
36.
90 times 2/5 (or 0.4) is equal to 36
Y - 2 = -3x + 12
3x + y = 14