Mirror

When Eric stands upright in front of his bathroom mirror, he can see down to his navel. If he takes a few steps back, can he now see: (a) More of himself (b) The same amount (c) Less of himself? (Source: Guardian)

Half...

I gave half of my DVDs and one half of a DVD to Wayne. Then, I gave half of the remaining DVDs and one half of a DVD to George. Finally, I gave half of the remaining DVDs and one half of a DVD to Mar and nothing left to give Peter. How many DVDs did I have?

+ - / *

Using only "+", "-", "/" and "*" operations and the numbers below once, obtain 952:

3, 6, 25, 50, 75, 100

Pills

1. A drugstore received a shipment of ten bottles of certain drug. Each bottle contains one thousand pills. By mistake, the pills in one bottle are each 10 milligrams to much. How many times do you need to use scale to find the faulty bottle?

2. Six months later, the store received another 10 bottles of the same pill. This time there are any number of bottles that were filled with pills that were 10 milligrams to heavy. How many times do you need to use scale to find faulty bottles?

Source: Aha!: a two volume collection, by Martin Gardner