Finding the surface area of a rectangular trunk will require you to take some very precise measurements. Find the surface area of a rectangular trunk with help from a professional private tutor in this free video clip.

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Finding the surface area of a rectangular trunk will require you to take some very precise measurements. Find the surface area of a rectangular trunk with help from a professional private tutor in this free video clip.

Part of the Video Series: Math Questions & Answers

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Hi, I'm Rachel, and today we're going to be going over how to find the surface area of a rectangular trunk. Let's start off by looking at our image of the trunk, and you an have your trunk, you can draw a dotted line to show where it would be there. So, let's, you have to know the three dimensions. This width, length and height of the trunk. I like to picture it like you have two of everything. When you're doing surface area, you're doing the area of the entire surface. It's different than the volume, which is everything inside as well, the whole volume, this is just the surface area, what's on the surface. So it's going to be each rectangle added together. So, here the height, let's make this five. So, we're going to add the rectangles together. So we have two times four, that's one rectangle, we have this rectangle on the bottom, which you can see, which is four times five, and then there's the other rectangle of two times five in the back. So you use each possible combination for each number. But then, you have each rectangle twice. So you have to multiply everything by two. And then you're going to add them all together. So, we have two times four is eight, times two is going to be 16. Four times five is 20, times 2 is going to be 40. And two times five is 10, times 2 is going to be 20. So, then we just add them all together to get the whole surface area. We end up with a six, one plus four is five plus two is seven, and that is the answer to the surface are of this rectangular prism. I'm Rachel, and thanks for learning with us today.