Three closed boxes have either white marbles, black marbles or both, and they are labeled white, black and both. However, you’re told that each of the labels are wrong. You may reach into one of the boxes and pull out only one marble. Which box should you remove a marble from to determine the contents of all three boxes?
The one labeled both. Since you know it’s labeled incorrectly, it must have all black marbles or all white marbles. After you determine what it contains, you can identify the other two boxes by the process of elimination.
I’m not the sort that’s eaten, I’m not the sort you bake,
Don’t put me in an oven, I don’t taste that great,
But when applied correctly, around me you will find,
Problems are so simple when my digits come to mind.
When Julian and Penelope met, one was half the others age plus seven years. Ten years later when they married, Penelope was thirty, but this time one was nine tenths the age of the other. How old was Julian? (No fractions or partial years, whole numbers only).