A bag contains red, blue, and green marbles. There are 24 in total. There are twice as many red marbles as blue ones, and half as many green marbles as blue ones. How many blue marbles are there?
8
Let blue be b. Red is 2b, green is 0.5b. Total = b + 2b + 0.5b = 3.5b = 24? Wait, 3.5 doesn't divide 24 evenly. Let's adjust: total 21. b + 2b + 0.5b = 3.5b = 21 -> b = 6. Red = 12, Green = 3. Let's restate with 21 marbles.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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