Answer: You meant a picture?
Step-by-step explanation: The model is here:
flooring a value, simply means, dropping it to the closest integer, so for the floor function or ⌊x⌋, that means
⌊ 2.5 ⌋ = 2
⌊ 2.00000001 ⌋ = 2
⌊ 2.999999999999⌋ = 2
⌊ -2.0000000001⌋ = -3
⌊ -2.999999999999⌋ = -3
let's recall that on the negative side of the number line, the farther from 0, the smaller, so -1,000,000 is a tiny number compared to the much larger -1.
⌊ -5.2 ⌋ = -6.
Answer: a = 
We want to isolate a. Add both sides by 2. Then we get u + 2 = 2a. To get just a, we can divide by 2 to get (u+2)/2.
Hope that helped,
-sirswagger21
Pairs, in this case, relates to a group of 2 or more. We have 6 friends. Let's call them A,B,C,D,E,F. This will allow us to make a [some sort of] combination tree:
1. ABC against DEF
2. ABD against CEF
3. ABE against CDF
4. ABF against CDE
5. ACD against BFE
6. ACE against BDF
7. ACF against BDE
8. ADE against BCF
9. ADF against BCE
10. AEF against BCD
I believe there are 12 combinations... I just can't think of the last 2 though.
