SOLUTION: 2. The Great Pyramid at Giza was originally 483 feet tall, and it had a square base that was 756 feet on a side. It was built from rectangular stone blocks measuring 7 feet by 7 fe

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Question 149168: 2. The Great Pyramid at Giza was originally 483 feet tall, and it had a square base that was 756 feet on a side. It was built from rectangular stone blocks measuring 7 feet by 7 feet by 15 feet. Such a block weighs seventy tons. Approximately how many tons of stone were used to build the Great Pyramid? The volume of a pyramid is 1/3 the base area times the height.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
First, let's find the volume of one stone block:

V=l%2Aw%2Ah Start with the volume of a rectangular block equation


V=7%2A7%2A15 Plug in l=7, w=7, and h=15


V=735 Multiply

So the volume of one stone block is 735 cubic feet.




Now let's find the volume of the pyramid:

V=%281%2F3%29b%2Ah Start with the volume of a pyramid equation

Since the base is 756 feet, this means that the area of the base is 756%2A756=571536 square feet.

V=%281%2F3%29b%2Ah Start with the volume of a pyramid equation

V=%281%2F3%29%28571536%29%2A%28483%29 Plug in b=571536 and h=483


V=92017296 Multiply


So the volume of the entire pyramid is 92,017,296 cubic feet.


Now to find out how many blocks are needed to construct the pyramid, simply divide the volume of the pyramid by the volume of one block like this

92017296%2F735=125193.6

So rounding up, we need about 125,194 blocks to construct the pyramid.