There are 10 kids on the math team. Two kids will be selected from the team to compete in the state competition. How many ways a
re there to select the 2 competitors?
1 answer:
Answer:
45 ways
Step-by-step explanation:
Total number of kids = 10
We have to select the 2 kids
So the number ways to select two kids ![^{10}C_2](https://tex.z-dn.net/?f=%5E%7B10%7DC_2)
We know that ![^{n}C_r=\frac{n!}{r!(n-r)!}](https://tex.z-dn.net/?f=%5E%7Bn%7DC_r%3D%5Cfrac%7Bn%21%7D%7Br%21%28n-r%29%21%7D)
So ![^{10}C_2=\frac{10!}{2!(10-2)!}=\frac{10!}{2!\times 8!}=\frac{10\times 9\times 8!}{2\times 8!}=45](https://tex.z-dn.net/?f=%5E%7B10%7DC_2%3D%5Cfrac%7B10%21%7D%7B2%21%2810-2%29%21%7D%3D%5Cfrac%7B10%21%7D%7B2%21%5Ctimes%208%21%7D%3D%5Cfrac%7B10%5Ctimes%209%5Ctimes%208%21%7D%7B2%5Ctimes%208%21%7D%3D45)
So there are 45 ways to select 2 competitors
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Answer:
Theoretical, Experimental
Step-by-step explanation:
Theoretical Probability is what should happen.
Experiemtnal Probability is what does happen.
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