This problem from the Singapore Math series was posted on Facebook by Singapore TV personality Kenneth Kong. He wrote, “This question causes a debate with my wife …. and its a P5 question.” The Singapore Math curriculum is used by the country of Singapore with enormous success (their students are usually ranked at or near the top in international rankings). P5 is roughly the equivalent of 5th grade math in the U.S., but this question is actually from the recent Singapore and Asian Schools Math Olympiad, which is given to the top 40% of students in the country.
So, are you smarter than a 5th grade Singapore Math Olympiad student? (You can find the answer here.)