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Arithmetic Puzzles
Arithmetic puzzles are Mad Libs for math: fill in the blanks with numbers or operations to make the equation true.
Excel in math and science
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Concept Quizzes
What series of signs will make the following equation true: \[ 2 \, \square \, 2 \, \square \, 2 \, \square \, 2 = -6? \]
Excel in math and science
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It's hard to learn from lectures and videos
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Our wiki is made for math and science
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by Brilliant Staff
Which of the following series of signs will make the following equation true: \[ 2 \, \square \, 2 \, \square \, 2 \, \square \, 2 = 4? \]
Excel in math and science
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It's hard to learn from lectures and videos
Learn more effectively through short, conceptual quizzes.
Our wiki is made for math and science
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What series of signs will NOT make the following equation true: \[ 8 \, \square \, 8 \, \square \, 8 \, \square \, 8 = 0? \]
Excel in math and science
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It's hard to learn from lectures and videos
Learn more effectively through short, conceptual quizzes.
Our wiki is made for math and science
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examples, and problems from the community.
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by Brilliant Staff
How many different 3-tuples \((\square,\triangle,\star)\) of operators make the following equation true: \[6 \, \square \, (3 \, \triangle \, 2)=1 \, \star \, 1?\]
Details and Assumptions
- \(\square,\triangle,\star\) can be one of the four arithmetic operators: \(+,-,\times,\div.\)
- One kind of operator can be used more than once.
Excel in math and science
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Our wiki is made for math and science
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What series of signs will NOT make the following equation true: \[ 4 \, \square \, 4 \, \square \, 4 \, \square \, 4 = 16? \]
Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, conceptual quizzes.
Our wiki is made for math and science
Master advanced concepts through explanations,
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by Brilliant Staff