11,15,19,23
an = 11 + 4(n-1)
an = 11 + 4n - 4
an = 4n + 7
Answer:
-243
Step-by-step explanation:
(-3) (-3) (-3) (-3) (-3) = - 243

Hello!
Since this amount we are given an amount we need for 3 people, we just multiply each amount by four to get to 12.
12 cups of almonds
4 cups of raisins
1 1/3 cups of chocolate chips
I hope this helps!
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.