Answer:
4) 68cm³
5) 320cm³
Explanation:
To find the volume of a rectangular prism, we can multiply the length, width, and height of the figure.
For the first problem, we can divide the figure into two shapes and find the volumes separately. We can see that the dimensions of the top figure are 4×2×1. Multiply these together.
4 · 2 · 1 = 8
The volume of the top shape is 8cm³.
Next, we need to find the volume of the figure on the bottom. The dimensions of this shape are 10×3×2. Multiply these together as well.
10 · 3 · 2 = 60
The volume of the bottom shape is 60cm³.
Now that we have to volumes of both figures, we can add them together.
8 + 60 = 68
The total volume is 68cm³.
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For the next figure, we can find the volume of both prisms at once, since both have the same dimensions. We can solve for the volume with the length, width, and height, with the height multiplied by two. Imagine this as stacking the prisms on top of each other.
A single prism has the dimensions 5×8×4, with 5cm as the height. With the prisms stacked, the height will be 10cm. So, the dimensions will be 10×8×4. Multiply the dimensions together.
10 · 8 · 4 = 320
The total volume is 320cm³.
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Good luck ^^