Mike has 10 and a half cookies (10.5). Mike wants to share these cookies with 5 friends. How many cookies does each friend get. The answer is 2.1 one (Or 2 and 1 crumb I guess lol). You place the decimal point where ever it was originally so you would place it after the 2 and before the one. It's been a while since I've done one of these problems so sorry if I'm a little rusty.
Well, you could assign a letter to each piece of luggage like so...
A, B, C, D, E, F, G
What you could then do is set it against a table (a configuration table to be precise) with the same letters, and repeat the process again. If the order of these pieces of luggage also has to be taken into account, you'll end up with more configurations.
My answer and workings are below...
35 arrangements without order taken into consideration, because there are 35 ways in which to select 3 objects from the 7 objects.
210 arrangements (35 x 6) when order is taken into consideration.
*There are 6 ways to configure 3 letters.
Alternative way to solve the problem...
Produce Pascal's triangle. If you want to know how many ways in which you can choose 3 objects from 7, select (7 3) in Pascal's triangle which is equal to 35. Now, there are 6 ways in which to configure 3 objects if you are concerned about order.
Given:
The equation is:

Find-:
Binomials factor of the equation
Explanation-:
The quadratic equation,

Solve for factor

Then the factor is:

So, the factor is x + 4
Steps to simplify:
(2x + 3)(x - 7)
~Use FOIL to multiply
(2x * x) + (2 * -7) + (3 * x) + (3 * -7)
~Simplify
=2x² - 14x + 3x - 21
~Combine Like Terms
2x² + (-14x + 3x) - 21
~Simplify
2x² - 11x - 21 (Option 2)
Best of Luck!