The diagram below shows two identical, large squares divided into smaller squares.
Which area is larger, blue or green?
by
Chung Kevin
A swing is in motion with a girl sitting on it. If the girl stands up on the swing when the swing is at the lowest point, what happens to the time period of the swing?
by
Pranshu Gaba
If \[a + b = 5 + 5\] and \[\displaystyle \frac 1a + \frac 1b = \frac15 + \frac15,\] is it necessarily true that \(a\times b = 5\times5?\)
by
Pi Han Goh
There is exactly one ladybug in each cell of a \(5\times 5\) square, as shown in the figure. Then, each ladybug simultaneously flies into a randomly selected, adjacent square that shares an edge.
Is it possible that, after all the ladybugs have moved, there is still only one ladybug in each cell?
by
Áron Bán-Szabó
Peggy is a treasure hunter trying to open two treasure boxes. One box has 2 switches and the other has 4 switches. All of the switches are initially turned off. To open a treasure box,
- she must only change one switch at a time;
- she needs to register every possible combination exactly once.
Peggy successfully opens the box with 2 switches in the following manner:
The sequence in which Peggy toggles the switches
Can Peggy open the box with 4 switches?
Hint: What if Peggy's box had 3 switches instead?
by
Agnishom Chattopadhyay