Alright, let's convert to decimals for these calculations: fractions could get messy.
1/5 = .2
1/2 = .5
Imagine a rectangular solid in your mind. How many sides does it have?
6. In the image shown you have 3 facing you. In addition to those, there are 3 not shown. They will correspond to the calculations you make on the front, though, so all you have to do is double the values you get.
Area is length width, or length height, or width height. So:
A = 3.2 (length) 4.5 (height) for the front face of the rectangular solid(as well as the back face.)
A = 5 (width) 4.5 (height) for the right face of the rectangular solid (and the one on the left, away from you.)
A = 3.2 (length) 5 (width) for the top of the solid(and the bottom).
Calculating these values, we get thatÂ
A=14.4
A=22.5
A= 16
So that's 3 out of 6 values for the full surface area.
Like I said though, these values can merely be doubled for the complete area.
Add these three together:
14.4+22.5+16=52.9
multiply by 2 to account for the other 3 sides
52.9 * 2 = 105.8
105.8 is the surface area.
