Same as handshake problem.
Each of n persons plays against n-1 persons for a total of n(n-1)/2 games.
The division by 2 is necessary to avoid double counting the game A vs B and B vs A.
For n=8, then number of games played in the first round is 8(8-1)/2=28 games.
Answer:
There are 150 blue marbles in Alex's bag.
Step-by-step explanation:
Let 
, 
, 
be the quantities of red, blue and yellow marbles, respectively. From statement we derive three rational equations for initial and final ratios:
Initial ratio
(1)
(2)
Final ratio
(3)
After some algebraic handling we get the following system of linear equations:
(1)
(2)
(3)
The solution of the system of linear equations is:
, 
, 
There are 150 blue marbles in Alex's bag.
Answer:
x=7
Step-by-step explanation:
5x=35
x=7
Answer:
488 in^2
Step-by-step explanation:
So just find the factors of 90
90=2 times 3 times 3 times 5
so the factors could be
2,3,15
2,9,5
6,3,5
10,3,3
there are 4our
