ELI5: Explain Like I'm 5

Necklace problem

Okay kiddo, imagine you like necklaces just like your mom or your sister. You have many different colored beads and you want to create a necklace that looks unique and pretty.

Now, you have to decide how many beads you want to use and the order in which you want to put them on the cord. But you want it to be very different from any necklace you have ever seen before!

This is where the necklace problem comes in. Scientists and mathematicians like to solve problems like this by trying to figure out how many different combinations are possible.

So, if you have 3 beads, you can put them on the cord in different orders like red, blue, green, or green, blue, red or blue, red, green. There are actually 6 different ways you could do it!

But what if you have 4 beads? Now there are 24 different ways to arrange the beads. As you can see, the number of possible combinations grows very quickly as you add more beads.

This kind of problem is called a combinatorial problem, and it can be solved using math called permutation and combination. Scientists and mathematicians use this to solve more complicated problems in many different fields.

So the next time you string some beads onto a necklace, think about all the different ways you could arrange them and remember the necklace problem!