Grades 11-12 Video Solutions 2026-2026_11-12

Video Transcription

Video Summary

The task asks for the minimum number of 2x2 color-flip operations needed to make a 4x4 board all white. Since the top-left and bottom-right tiles each must be included in an operation, at least two moves are needed there. However, the remaining 8 dark tiles cannot be eliminated in just 2 more moves, so 4 moves is impossible. The correct minimum is 6 operations. Therefore, the answer is <strong>B, 6</strong>.

Keywords

2x2 color-flip

4x4 board

minimum operations

all white

6 moves