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sattari [20]
2 years ago
7

A tennis tournament has 2n contestants. We want to pair them up for the first round of singles matches. Show that the number of

different ways in which first round matches can be conducted is
Mathematics
1 answer:
ddd [48]2 years ago
4 0

There are

\dbinom{2n}2 = \dfrac{(2n)!}{2! (2n-2)!}

ways of pairing up any 2 members from the pool of 2n contestants. Note that

(2n)! = 1\times2\times3\times4\times\cdots\times(2n-2)\times(2n-1)\times(2n) = (2n-2)! \times(2n-1) \times(2n)

so that

\dbinom{2n}2 = \dfrac{(2n)\times(2n-1)\times(2n-2)!}{2! (2n-2)!} = \boxed{n(2n-1)}

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svetlana [45]
You have to choose 1 sort of cheese from 3 ( 3 ways ). Also you have to choose 3 toppings from 12 different toppings:
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Answer:
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3 years ago
Gavin borrowed $250 from his parents to buy a new mp3 player. Each week he pays his parents back $10. The function, m(w) = 250 –
Kryger [21]

Answer:

m=25

Step-by-step explanation:

You want to divide 250 by 10 to find the number of weeks it would take him to pay back his parents. which would be 25. It would take Gavin 25 weeks to pay his parents back. m(w)=0 just is telling you the worth of that part of the equation.

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3 years ago
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8 0
3 years ago
What is the value of x
Gekata [30.6K]

Answer:

x=20

Step-by-step explanation:

Since angle RTS is a right angle, we have three similar triangles.

Thus, \frac{x}{25} = \frac{16}{x}

Cross Products, x^2=400

Take the square root: x=20

4 0
3 years ago
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Hey I need help a lot of help
Neko [114]
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