Abby, Brian, Charles, Dennis and Eason have 50 stickers altogether.
Abby has the most stickers — she has 12 stickers.
In second place (tied) are Brian and Charles.
In third place is Dennis.
In fourth place is Eason, with 6 stickers.
How many stickers does Dennis have?
This is part of a series on Homeschool Math Challenging Puzzles, suitable for Grades 2-4. (Of course, students of other grades are also welcome to try them out.) The questions are suitable for:
- Homeschooling for gifted kids
- Preparation for GEP (Gifted Education Programme) screening and selection tests
- Preparation for Math Olympiad
- Puzzles for kids interested in math but find school work too easy.
For this type of questions, the easiest way to do is “trial and error”, also known as “guess and check”.
Firstly, lets check how many stickers B, C, and D have together:
|9||9||14||32||Wrong! Since D is more than A|
|10||10||12||32||Wrong! Since D is tied with A|
|12||12||8||32||Wrong! Since B, C is tied with A|
For guess and check, the most important thing is to be systematic, rather than guess wildly. For instance, we can systematically increase our guesses for B, C.
We can see that the only logical answer is:
Answer: Dennis has 10 stickers.