Some of us just don't understand maths. No matter how hard we try, we simply cannot nail it. So if you fall under this category, I get it. But for the ones who don't, I wonder why they're finding it a struggle to solve this. It was created for Singapore and Asean Schools Math Olympiads, a competition for super intelligent 14-year-old math-letes.
Take a look:
The question was to be used in the test, but was leaked and reported by a TV presenter in Singapore. Give it a try. You might just crack it.
For the rest of us who have no idea whatsoever, here's the break down of the problem as put by Singapore's Study Room :
First we need to figure out if Albert knows the month or the day. If he knows the day, then there is no chance that Bernard knows the birthday, so it must be that Albert knows the month.From the first statement, we know that Albert is sure that Bernard doesn't know the birthday, so May and June should be ruled out (the day 19 only appears in May and the day 18 only appears in June). In other words, if Albert had May or June, then he cannot be sure that Bernard doesn't know, since Bernard could have had 18 or 19.Following that statement, Bernard knows that May and June are ruled out.Then, Bernard is able to know which month it is. So it must be either July 16, August 15 and August 17 (not 14th as then he can't know).Since Albert subsequently can also be sure of the date, he must know it's July. If it's August, he can't be sure as there is August 15 and 17.So the answer is July 16.
Amazing right? Were you able to crack it?