Lucky Tram Tickets
Tram tickets carry six-digit numbers from 000000 to 999999, leading zeros included, so there are one million tickets. A ticket is lucky if the sum of its first three digits equals the sum of its last three. How many tickets are lucky? Give an integer.
Related problems & prerequisites
Worth solving first
- PINs Summing to Twenty 3.0/10
- Stars and Bars 3.0/10
- Threes and Fives 2.0/10
Source: The Soviet "lucky ticket" problem, a classic in wide circulation; no traceable original source. Statement written for AxiomIQ.