Aslan's Fleas
(page 74)

The most recent (June 2005) solutions come to us from a sixth-grade class Hong Kong International School (HKIS). I won't show you all of them, but here is a sample. These are not necessarily right, remember, and are not always the clearest. But each has some interesting logic in it. Is the logic correct?

Many of the solutions from HKIS used guess and check. That's a really good strategy, but if you use it, how do you know that yours is the only solution?

The answer is 27 fleas. The number of fleas had to be able to be divisible by three as it had to be divisible by two thirds and come out as a whole number. The numbers divisible by three are:

3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60 ...

We tried all the numbers and the one that fit the criterea that the fleas of Rover and spot equals 35, was if Aslan had 27, Rover had 18, Prince had 21 and Spot has 17.

From, 6 grade students from HKIS ( Ching-lun, Nicola, Solomon, and Se Choong)


Dear person,
Me and my friend Garvin have found out the answer to Aslan's fleas, We are grade six students at HKIS. We think the answer is 27 flies

First we looked at the important clues:
Rover has two thirds as many fleas as aslan

Spot has the fewest fleas

If all prince's fleas hopped into Rover, Rover would have 39 fleas

Rover and spot have 35 fleas between them

So, since spot has the fewest fleas, 35 divided by 2 is 17r1, so we give rover the extra flea so spot has the least


Then, it says that rover has two-thirds the fleas of aslan, so Eigteen divided by two is nine. 9 times three is 27, so aslan has 27 flies

From Rohan and Garvin

Hi there,

We are the Sixth Graders from Hong Kong International School. We're here to give you a solution to Aslan's Fleas Problem Solving equation. The answer we got is that Alan got 27 fleas. We first wrote out:

P+R+ 39

If you add it all together, you'll get 112. (2P+2S+2R=112). We then have to divided by 2 so then it'll be P+R+S which equals 56. We then guessed and checked and found the answer to Rover, Spot and Prince.


As you said Rover has two-thirds as many fleas as Aslan. 18 will have to be divided by 2 and then be multipled by 3 which equals 27.

Here's an older solution from a student at Pleasant Run Middle School in Cincinnati, Ohio:

Hi, my name is Lauren and I sent you this solution for the Aslan's Fleas problem on page 74. (i think.) Mrs. Lowe's 6th grade math class- '98 and I figured this out. This is our solution:

Spot- 17

Prince- 21

Rover- 18

Aslan- 27

All the clues that were given meet the our solution. Please try and submit ours and we would be very grateful. Thank you for your time.

Thank you, Lauren!

I hope I get more from you (and your group, I presume, right?) or other kids in your class as you do more problems.

When you send me more, remember: sometimes people look at these to see if they're right. But other times they come to the site because they're confused. So next time, think how you can describe HOW you got the solution, so the confuse people can figure it out for themselves.

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