UNDERGROUND

Your right elbow. You can try it yourself if you’re not convinced, but unless you have a broken arm or an incredibly flexible ulna, you won’t reach it.

87 is the common answer to this, but it has to be flipped upside down, so I consider L8 more correct.

If you flip the numbers horizontally by 180 degrees:

86 87 88 89 90 91

You see that the blank spot is 87, counting from 86 to 91. However, you need to flip it around, so it becomes L8.

1/2 probability. This has been know to cause raging debates and is known as one of the variations of the Boy or Girl paradox. This variation is more straightforward because knowing the position of the child leaves only two possibilities – the other child is a boy or a girl, each of which have a 1/2 probability.

Another variation of this can be found here.

A mango costs 15 cents. The logic is 3 cents per letter.

Meat. The rest of the details were merely distractions. Butchers weigh meat at a butcher shop.

AJCTA. These are the first letters from the nursery rhyme, “Jack and Jill Went Up The Hill”. AJCTA represents, “and Jill came tumbling after”.

Zero.

None. Moses didn’t have an ark, Noah did (and yes, he took 2 of each animal).