How many different committees of 5people can be chosen from 10 people
Solution:
Let's give each people one number: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10;
We can write it like set: "A={1,2,3,4,5,6,7,8,9,10}", this is set with 10 elements. Now, we need to find number of subsets of set A which equal number of different committees with 5 people:
"N=\\frac{n!}{(n-m)!m!}" - this is formula of number of subsets with m elements in set with n elements.
"N=\\frac{10!}{(10-5)!\\times5!}=\\frac{10!}{5!\\times5!}=\\frac{6\\times7\\times8\\times9\\times10}{5!}=252;"
Answer:
"N=252" -number of different committees with 5 people.
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