plural of trolley problem

(US, humorous) Used to report that a (major) problem has occurred.

(mathematics) The problem of finding two disjoint sets A and B of n integers each, such that ∑_(a∈A)aⁱ=∑_(b∈B)bⁱ for each integer i from 1 to a given k.

plural of year 2000 problem

plural of file-drawer problem

plural of one-banana problem

plural of first world problem

plural of two-body problem

plural of dial-a-ride problem

plural of chicken-and-egg problem