Answer:
The total number of games won by Unicorn is 40.
Step-by-step explanation:
- We are given with a word problem
- We are asked to find the number of unicorns played during the season
- We can do this in two steps
Step 1: Finding the win percentage
Step 2: Finding the number of unicorns played during the season
Step 1 of 2
Let the number of games played by unicorn be x.The unicorn won 60% of the first x-10 games That is 
Combining the 8 games we get,

Step 2 of 2
The unicorn totally won 65% of the games played.
That is 
Equating both the equation gives

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.
Answer:

Step-by-step explanation:
Given




Required
Find the height
The volume is calculated as thus:

This gives

Apply difference of two squares


Subtract 15 from both sides

Using a calculator to factorize, we have:

Split
or 
or 
x has complex roots for 
Hence:

Recall that:


Answers:
1) 6
2) 5
3) 8
4)5ab^5