Your method is good, but in my view overthinks it - I just looked at it, and let what seemed like the right solution just pop into my head - and it was. It felt

Your method is good, but in my view overthinks it - I just looked at it, and let what seemed like the right solution just pop into my head - and it was. It felt like 27 would be the answer. I know that seems woolly as all hell, but that’s the nature of running stuff at a level that can’t be consciously interacted with or directly queried. A quick conscious mental multiplication verified it. Intuition is incredibly underrated - I have learned to trust the first damned fool thing that pops into my head, before any conscious thought has had time to get moving and therefore interfere. It’s usually correct, regardless of context - and when it goes wrong, it’s because I accidentally allowed myself to think and reason. It’s in the same category as “walking away from a problem”, in my view - you can’t solve it, you go grab a coffee, and while you’re looking for the sugar the answer is just suddenly there in your head, because you stopped running the CPU-intensive conscious process, and let the background workers catch up. Conscious thought is great for producing outputs for other humans to then work with. Unconscious through this great for… everything else. We do incredibly complex things all the time - catching a ball, walking upright, looking in the direction of that sudden sound - but typically run all of the gnarly logic in an abstraction layer within a virtual machine, rather than on the hardware that was designed to run it natively. No end of trouble at school where I wouldn’t just not show my working, but couldn’t - but the real world fortunately doesn’t particularly care about the means, just the ends.