Question: Arranging Buttons

Comment on Arranging Buttons

Here can we approach this way :

Since total no. of buttons are 6
Red buttons =2
Blue buttons =2
Green buttons = 2

Therefore the no. of ways = 6C2 * 4C2 * 2C2 =90 ways
greenlight-admin's picture

It took me a while to determine what you are doing with each step in your solution.
I think I understand now.
There are 6 places each button can go.
So, first we can choose two spaces to place the two red buttons.
We can accomplish this in 6C2 ways.
There are now 4 spaces left.
Next, we'll choose two spaces to place the blue buttons.
We can accomplish this in 4C2 ways.
There are now 2 spaces left.
Finally, we'll choose two spaces to place the green buttons.
We can accomplish this in 2C2 ways.

Great strategy!!!

Cheers,
Brent

Apology, just dashed straight to the solution.

I'm confused because I thought this question was similar to the books on a shelf question.
greenlight-admin's picture

Those two questions, although similar, have a big difference.

In the books on a shelf question, the books in one topic (e.g, History) are DIFFERENT. For example, one history book might be about the Civil War, which another history book might be about the War of 1812

In the above question, the two red buttons are IDENTICAL, the two blue buttons are IDENTICAL, and the two green buttons are IDENTICAL.

Cheers,
Brent

Add a comment

Have a question about this video?

Post your question in the Comment section below, and we’ll answer it as fast as humanly possible.

Change Playback Speed

You have the option of watching our videos at various speeds (25% faster, 50% faster, etc). To change the playback speed, click the settings icon on the right side of the video status bar.

Let us Know

Have a suggestion to make our course even better? Email us today!

Free “Question of the Day” emails!