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Excel in math and science
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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,
examples, and problems from the community.
Used and loved by 4 million people
Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.
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A full bottle of green tea weighs 350 grams.
With half the tea consumed, it weighs 200 grams.
What is the weight of the empty bottle?
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,
examples, and problems from the community.
Used and loved by 4 million people
Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.
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by
Chung Kevin
When placed on a scale, a container of water measures \(\SI{20}{\kilogram},\) while a steel ball measures \(\SI{2}{\kilogram}.\) Now, the steel ball is dipped into the water, as shown in the diagram above. What will be the new reading on the scale?
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,
examples, and problems from the community.
Used and loved by 4 million people
Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.
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by
Rohit Gupta
In a circle, a chord divides the diameter perpendicularly into lengths of 1 and 9. What is the length of the chord?
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,
examples, and problems from the community.
Used and loved by 4 million people
Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.
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That seems reasonable.
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by
Stuti Malik
Mother came home and saw a broken vase. She immediately questioned her 4 children, who replied as follows:
Alex: "It wasn't Brian. It was Daniel."
Brian: "It wasn't Charlie. It wasn't Daniel."
Charlie: "It wasn't Daniel. It was Brian."
Daniel: "It was Charlie. It was Brian."
It is known that each of them told one true and one false statement. Who broke the vase?
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,
examples, and problems from the community.
Used and loved by 4 million people
Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.
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by
Chung Kevin
How many triangles are there in the figure above?
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,
examples, and problems from the community.
Used and loved by 4 million people
Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.
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by
TJ Evert