Grades 3-4 Video Solutions 2023-2023_3-4

Video Transcription

Video Summary

Hermione, Harry, and Ron enter the common room one at a time under specific constraints: Hermione can't be first, Harry can't be second, and Ron can't be third. Upon analyzing possible sequences, if Hermione is second, Ron must be first and Harry third. Conversely, if Hermione is third, Harry must be first and Ron second. Due to these restrictions and limited options, only two valid entry sequences exist: Ron-Hermione-Harry and Harry-Ron-Hermione. Therefore, the total number of possible orders is two.

Keywords

Hermione

Harry

Ron

entry sequence

constraints