Puzzle #217 Solution: Bleach Leave a reply Spoiler Inside: Solution to Puzzle SelectShow> I stumbled on this, and then realised how to solve it. 4.1 is 3% of what number? 4.1 / 3% = 4.1 / 0.03 = 136 2/3 which rounds to 137. Subtracting the 100 parts of bleach leaves 37 parts water. Close to 100:37 is 8:3. Please be careful with dealing with bleach. Keep bleach away from ammonia compounds to avoid chlorine gas being released.