Hello! To do this, first find the volumes of the tanks (how much water they can hold), then how much water is in tank P, and finally, how full tank Q would be.
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To find the volume of a rectangular prism, you multiply the length, width, and height.
Tank P: 15 * 12 * 8 = 1440 cm³
Tank Q: 10 * 20 * 6 = 1200 cm³
Now, we know that tank P is half full. Therefore, the volume of the water must be half that of the whole volume of tank P. We know the volume of Tank P is 1440 cm³, so just divide by 2.
1440/2 = 720 cm³
Therefore, there is 720 cm³ amount of water in Tank P. Finally, find how much of Tank Q this amount of water would occupy.
Set up a fraction to do this:
720 / 1200 = 0.6 = 3/5
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Therefore, 3/5 of Tank Q is filled.
Hope this helps!