Well, the perimeter is the rim of the rectangle and you can use the rim to find the area... but, First you have to find the length and the width
if the width is two times the height when you flip that you get that the height is half of the width
So first you find that half of 24 is 12... this is our width
Now, what is half of 12... 6, this is our height
simple math tells us that to find the area you multiply that height and the width
6 * 12 = 72
so the area of the poster is 72 inches