Answer:

Step-by-step explanation:
Let's start by using change of base property:

So, for 

Now, using change of base for 

You can express
as:

Using reduction of power property:


Therefore:

As you can see the only difference between (1) and (2) is the coefficient
:
So:


Sharing with three friends:
1/24 of original pie
Sharing with little brother:
1/12 of original pie
9 is the answer 15-6 is 9