People have been baffled by the solution to an apparently complicated maths puzzle, and not to toot my own horn dear reader, but it's not really that difficult.
Sometimes you get these maths questions which are actually just giant tricks designed to bamboozle you unless you twig which branch of logic it's tugging on, but this question is actually just testing your mathematical aptitude.
Posted online by @your.big.brain.tutor, she explained the maths puzzle thusly: "One number is five more than another number.
"Three times the greater plus twice the lesser is 30. Determine the numbers."
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If you don't want to know what the answer is, then go and figure it out now then come back to check if you were right.
She explained that the bigger number that was 'five more than another number' would be 'x', so x must be equal to 'five plus y'.
Still with us so far? Good.
That'd mean that 3x + 2y would equal 30, and the tutor used the 'substitution method' to make it all work.
The sum was 3(5+y) + 2y = 30, and since three times five is 15 that meant 15 + 5y equalled 30, and if you knock 15 off either side of that equation then 5y = 15, then you divide those by five to find the value of y, which is three.
If y is three and x is five more than y, then x must be eight.
Lo and behold, eight multiplied by three is 24 and two lots of three is six, putting them all together you get 30 and the comforting knowledge that you got the right answer.
While lots of people said they 'still don't get it' and they 'just got brain damage' from hearing that explanation, it's really not all that difficult.
If, like me, you wanted to do it with a less refined method than that, you could deduce that since three lots of x plus two lots of y were equal to 30, then x could not be 10 or higher or six or lower.
Assuming that x and y weren't getting into decimal f**kery, that'd leave you with just seven, eight or nine as the correct answers, and you could quickly work out that x must be equal to eight.
That's certainly not the correct method to be working out this equation but it does still bring you to the right answer, and I haven't been in a maths class for over 10 years so anything that requires a level of complication beyond the grid method is quite annoying.
Of course, had the answer been something other than a whole number then it would have required the proper calculation, whereas my method would just have given you a reasonably rough idea of where to land.
Don't you wish you'd paid more attention in maths?
Joe Harker