Sum of the Minima
For each of the C(10, 3) = 120 three-element subsets of {1, 2, ..., 10}, write down its smallest element. What is the sum of all 120 numbers written? Give an integer.
Related problems & prerequisites
Worth solving first
- Triangles in a Hexagon 6.0/10
- Strides of Any Length 5.4/10
- Lines and Circles 5.0/10
Source: Classic counting exercise in wide circulation; no traceable original source. Statement written for AxiomIQ.