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, interactive explorations.
Used and loved by over 6 million people
Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.
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, interactive explorations.
Used and loved by over 6 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?
by
Chung Kevin
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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?
by
Rohit Gupta
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In a circle, a chord divides the diameter perpendicularly into lengths of 1 and 9. What is the length of the chord?
by
Stuti Malik
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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?
by
Chung Kevin
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How many triangles are there in the figure above?
by
TJ Evert
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