Which Ring? Even and Big
Read the puzzle
Two overlapping rings are labelled EVEN NUMBER (left) and MORE THAN 50 (right). The number 12 sits in the left ring only, 91 in the right ring only, and 33 outside both. Options: A) 47, B) 38, C) 75, D) 64. Which number belongs in the middle, where the rings overlap?
Which number belongs in the middle?
It must be even and more than 50.
D
64 is even AND more than 50. 38 is too small; 47 and 75 are odd.
How to solve it
A number in the middle must pass both labels: it must be even and it must be more than 50. Test each option against both.
Even or odd: 47 ends in 7, so it is odd. 38 ends in 8, even. 75 ends in 5, odd. 64 ends in 4, even. That leaves 38 and 64.
More than 50: 38 is less than 50, so it fails. 64 is more than 50, so it passes.
Only D, 64, passes both tests, so it goes in the overlap.
The usual wrong answer is B, 38, because it is even like the 12 already in the left ring. It belongs in the left-only part with 12. The other trap is C, 75, which is big like 91 but odd, so it sits in the right-only part.
Quick check using the examples already placed: 12 is even but not over 50, 91 is over 50 but odd, and 33 is neither, so it stays outside both rings.
Learn the method: Process of Elimination in Puzzles: Rule Out Until One Is Left
