1. ## story problem

I'm horrible with story problems but this one just kind of confuses me with the wording its something I found on the net can anyone help?

A man has a miniature Pyramid of Egypt. It is 3 inches in height. The man was invited to display it at an exhibition. He felt it was too small and decided to build a scaled-up model of the Pyramid out of material whose density is (1/8) times the density of the material used for the miniature. He did a "back-of-the-envelope" calculation to check whether the model would be big enough.

If the mass (or weight) of the miniature and the scaled-up model are to be the same, how many inches in height will the scaled-up Pyramid? Give your answer to two places of decimal.

2. Originally Posted by flyingsilverschoo
I'm horrible with story problems but this one just kind of confuses me with the wording its something I found on the net can anyone help?

A man has a miniature Pyramid of Egypt. It is 3 inches in height. The man was invited to display it at an exhibition. He felt it was too small and decided to build a scaled-up model of the Pyramid out of material whose density is (1/8) times the density of the material used for the miniature. He did a "back-of-the-envelope" calculation to check whether the model would be big enough.

If the mass (or weight) of the miniature and the scaled-up model are to be the same, how many inches in height will the scaled-up Pyramid? Give your answer to two places of decimal.
Assume the pyramid is solid. Then if the linear measurements are scaled by
a factor lambda, then the volume is scaled by lambda^3.

So let the scale factor be lambda.

For the masses to be the same if the large pyramid has a density 1/8
of the small, then the volume of the larger must be 8 times that of the
smaller. So lambda^3=8, and so lambda=2.

Hence the height of the scaled up pyramid will be 6 inches.

RonL

3. thanks I was just starting to think it would be 24inches because multiply by 8 so thanks