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I think a little bit of algebra gives the solution quite easily without programming. But here’s a program that verifies the solution.

Solution:You ordered 3 tetrahedra, and asked for an increase in size of 50%.Expanding the cubic equations and cancelling common terms leads to the equation:

f=n/ 6, wherenis a positive integer greater than 2 andfcan be expressed as a whole number percentage. This quickly leads to the solution:n= 3,f= 50%.