Not too long ago a program on Nova spotlighted a successful attempt to reconstruct a modern day pyramid near the great pyramids on the Giza Plateau. Over a several week(3) period, using the same methods they thought were used in the construcion of the Giza Pyramids, they were successful in building a pyramid of 186 stones(same size as the  smallest in the Great Pyramid)that was 20 feet high. I decided to compare the performance on this new pyramid with the Great Pyramid to see how long using the methods of the new pyramid builders it would take them to construct the great pyramid. Here is what I found out.

Assumptions

New Pyramid Construction(actual)
44 workmen
186 stones
3 weeks

Great Pyramid
2.4 million stones

Problem

Solve the equation for identifying the number of workmen
and time required to build the great pyramid at the same performance
rate as the new pyramid.

Performance Solution Equation - Time
186/3 = 2.4M/X
X = 38,710 weeks or 744 years

What this says is that at the same performance rate of 3 weeks to dress and lay 186 blocks how many years would it take to build a pyramid with 2.4 milllion. (Note: This does not take intoconsideration the additional complexifying aspects of scaled logistics and coordination or size.) It also suggests that that at
the same productivity ratio that it would have taken 567,742 workmen to achieve the same result on the larger pyramid over 744 years.

While these are straight line projections, and are simplfied, they do point to a potential missing element in the puzzle faced with the problem of discovering the design, processes, tools and manpower used in the construction of the Giza Pyramids.

Except for the simplified approach, if I have made any mistake in the
math let me know.