Answer:
1176
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Explanation:
First, calculate the volume as if it was a full rectangle.
Volume formula:
length x width x height
16 x 6 x 21 = 2016
(this is the volume if this was a full rectangle)
Now to calculate the size of the missing part we do the same thing
10 x 6 x 14 = 840
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To work out the volume of this shape, we need to subtract the volume of the missing part from the volume of the rectangle
2016 - 840 = 1176
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I hope this helped :-)