Counting will get you nowhere. Try a little combinatorics instead. By Kenneth Chang A couple of weeks ago, I wrote about a viral math problem — 8÷2(2+2) = ? — that drew the disdain of many ...
Do you think you have sharp eyes and an even sharper brain? Here’s a fun challenge that will put your observation and problem-solving skills to the test! Optical illusions are not just fun to look at ...
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