I have a collection of coins totaling $1.00. If I have twice as many nickels as dimes and three times as many pennies as dimes, how many coins do I have?
Category: Math · Difficulty: hard
Hint: Set up equations involving the coin values.
Answer
20 coins
Explanation
Let d be the number of dimes. Then, nickels = 2d, and pennies = 3d. The total value is 0.10d + 0.10(2d) + 0.01(3d) = 1. The solution gives 20 coins.
This is a hard math riddle — a tricky one that takes a little thought. The answer is 20 coins.
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