Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
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Used and loved by over 6 million people
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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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Four open containers of equal volume are connected as shown.
If the capacity of the pipes is greater than the flowrate from the tap, which container will fill first?
by
Rohit Gupta
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\[ \begin{array} { l l l }
& A & B \\
+ & C & D \\
\hline
& E & F \\
\end{array} \]
In the above cryptogram, all the letters represent distinct digits.
What is the minimum possible value of the 2-digit integer \( \overline{EF}? \)
Note: In cryptogram problems, 0 is not allowed to be a leading (first) digit, since we would just not write anything in its place.
by
Chung Kevin
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If points \(A, B, C, D, E, F, G, H, I\) all lie on a circle, as shown above, find \[\angle A+\angle B+\angle C+\angle D+\angle E+\angle F+\angle G+\angle H+\angle I\] in degrees.
by
Rizky Souleekeen
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\[ \begin{array} { ccccccc }
1234 & 1243 & 1324 & 1342 & 1423 & 1432 \\
\vdots & & & & & \vdots \\
4123 & 4132 & 4213 & 4231 & 4312 & 4321 \\
\end{array} \]
The 24 distinct 4-digit numbers above have been listed out by arranging 1, 2, 3, and 4 in different orders. What is the sum of these 24 numbers?
\(\)
Hint: You do not need to list out all 24 numbers to find the sum.
From: Derek Niederman's Math Puzzles for the Clever Mind
by
Deva Craig
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\(\)
By using 2 straight lines, what is the most number of regions that we can separate the cross into?
Note: Using 1 straight line, it is possible to separate the cross into 3 regions.
by
Chung Kevin
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