In Ethiopia there are 20 premier league soccer teams. a) In one round how many games are there ?

b) If five of the teams represent one company, find the number of ways pairs of teams representing different companies can play a game.

In A Premier League there are 20 soccer teams.

(a)In One Round How Many Games Are There?

20 choose 2 = 20C2 = 190

(b) If five of the teams represent one company, find the

number of ways pairs of teams representing different companies

can play the game.

So there are 4 companies, each having 5 teams.

4 companies choose 2 = 4C2 = 6 ways

Choose a team of the company that's, say, been in business the

longest.

5 teams choose 1 = 5C1 = 5 ways

Choose a team of the other company,

5 teams choose 1 = 5C1 = 5 ways

Answer 6*5*5 = 150 ways.

given that triangle abc is transformed two times to get triangle

a"b"c"

first abc is transformed in to a'b'c' as follows:

the coordinates of a are (1,-1) and transformed into a'(-1,1)

similarly b (4,-2) became b'(-4,2) and

c(7,-2) became c'(-7,2)

i.e. (x,y) becomes (-x,-y)

this is nothing but reflection about a point here origin.

thus first transformation is reflection on the origin.

next is exactly shifting 3 units down

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