pull down to refresh

The crossings of the edges of the blue region happen exactly at the crossing points in the grid.
Previous iteration: #702560
72 cm2
The arcs are circles of the same radius offset by 6cm. That makes the white area in one square congruent to a white area in the adjacent square. Two full worth of blue are shaded.
reply
18x12 - 12x12 is 12(18-12) is 12x6 or 72
reply
True, but what led you down that path.
reply
Your hint about the congruent circle ⭕️
reply
Interesting
reply
Actually this is a routine question asked of 12-year-olds in our Primary School Leaving Examination. They are trained to employ such heuristic thinking
reply
American 12th graders would be almost universally stumped by this question.
reply
Sad, but true
reply
Well they aren’t trained to do it, that’s why
I should post some tough PSLE questions here. Every other year, a question gets featured in our national media because kids come out of the exam room crying, parents cry foul, and education personnel tell everyone to chillax. It’s all very dramatic haha
reply
Curious about that PSLE questions.
Happened here too for 수능, university entrance exam. Some questions end up being too difficult. And because one's whole future sounds depends on a single exam, this can lead to big emotions...
reply
While future in one exam
Sounds extreme
reply
The major Korean companies only hire from graduates from the top 4 colleges, if I’m not mistaken. Quite an immobile society in that sense
reply
That's a bit of a caricature, but it used to be pretty much like that. Slowly changing though. One of my recent students, not from any of those 4 unis, got hired without a problem by Samsung.
What do you do if you don’t attend a top 4 school?
Whole not while , dam autocorrect
reply
Sure, I will post one!
reply
No, they are trained to do it. Our government education is just a complete disaster.
reply
Maybe that is where I saw it. It took me a minute to figure it out.
reply
you were very fast.
reply
I happened to see the post pretty shortly after it went up.
reply
Me too. I think I have seen this puzzle somewhere, maybe a math olympiad?
reply
6x6x2=72
reply
Good effort! Haha
reply
what do you mean? look a the timestamps.
reply
Well you still solved it, right.
Ngl I had to rely on @Undisciplined’s explanation before I figured it out haha
reply
I solved it first. Not still.
reply
Sorry, my bad. Sats for you!
reply