Subject: Permutations and Combinations

Name: Sarah

Who is asking: Student Level: Secondary

Question: Arnold has a dollar coin, one dime, one quarter, one nickel, and a penny. The number of different sums of money that can be formed using three coins is...

Hi Sarah,

Since each of the coins has a different value you get a different sum for each choice of three coins. Thus the number of different sums is the number of ways of selecting 3 coins from 5 coins. This quantity, called a binomial coefficient, is sometimes denoted and sometimes and its value is

Can you write down all 10 different sums?

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