please help me , step by step explanation needed
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Explanation
Part (a)
The smaller pyramid up top is the result of slicing at the halfway point.
This leads to the ratio 1:2 when comparing small side to larger side.
Cube both parts of that ratio to end up with 1:8 as the volume ratio.
This means if the smaller pyramid was say 1 cubic foot in volume, then the larger pyramid has a volume of 8 cubic feet.
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Part (b)
Consider the case that,
The volume of the truncated base is 8-1 = 7 cubic feet.
The ratio of the smaller pyramid to the truncated base is 1:7