Grades 5-6 Video Solutions 2024-2024_5-6

Video Transcription

Question 25. Simon takes four cups out of the cupboard and puts them randomly on the four saucers. For each cup, there is exactly one matching saucer. Which statement is correct?  Notice how if three cups stand on their matching saucers,  the only available saucer for the fourth cup will be its own matching saucer.  Therefore, if there are three cups on their matching saucers, the fourth cup must also be on its matching saucer,  which means that it is impossible for exactly three cups to stand on their matching saucers.

Video Summary

In a scenario where Simon randomly places four cups on four saucers, each with one matching saucer, it is impossible for exactly three cups to be on their matching saucers. If three cups are correctly placed, the remaining saucer would automatically match the fourth cup, meaning all four cups would be correctly placed. Therefore, the situation where exactly three cups are on their matching saucers cannot occur.

Keywords

matching saucers

cup placement

impossible scenario

four cups

derangement