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counting and probability intermediate
Problem
Steve has one quarter, two nickels and three pennies. Assuming no items are free, for how many different-priced items could Steve individually pay for with exact change?
Solution
Steve can use no quarters or one quarter, for two possibilities.
Steve can use 0, 1, or 2 nickels, for three possibilities.
And Steve can use 0, 1, 2, or 3 pennies, for four possibilities. That gives possible combinations. But we must remove the combination where Steve does not use any coins, leaving us with
Steve can use 0, 1, or 2 nickels, for three possibilities.
And Steve can use 0, 1, 2, or 3 pennies, for four possibilities. That gives possible combinations. But we must remove the combination where Steve does not use any coins, leaving us with
Final answer
23