Answer:
4L-12
Step-by-step explanation:
let's assume the length = L
then the width of the rectangle is L - 6
perimeter = 2× (a+b)
where "a" and "b" are the length and the width of the rectangle.
so perimeter = 2× (L + L - 6)
2 × ( 2L - 6)
4L - 12
3 hours
4.5*(2/3)
= 3 hours