What is 0.7 in simplest form

A80-foot piece of siding is cut into three pieces so that the second piece is four times four times as long as the first piece and the third piece is five times as long as the first piece. if x represents the length of the first piece, find the lengths of all three pieces.

Which statements are true? see picture

Write an equation for the function that includes the points (1,4/5) and (2,2/3)