Grades 11-12 Video Solutions 2025-2025_11-12

Video Transcription

Video Summary

The problem involves finding a digit \( n \) for which the number formed by appending 18 to \( n \) and \( n \) is divisible by 18. The approach involves testing divisibility rules: \( n \) must be divisible by 3 and even. By breaking down the number into digits and applying these divisibility constraints, the solution shows that \( n \) must equal 6, as it is the only even number divisible by 3. Thus, the correct answer is option A: there is exactly one such \( n \).

Keywords

divisibility

digit problem

number theory

even number

solution