Brain Teasers / Games

Miracle Mountain

A hiker climbs all day up a steep mountain path and arrives at the mountain top where he camps overnight. The next day he begins the descent down the same trail to the bottom of the mountain when suddenly he looks at his watch and exclaims, "That is amazing! I was at this very same spot at exactly the same time of day yesterday on my way up."

What is the probability that a hiker will be at exactly the same spot on the mountain at the same time of day on his return trip, as he was on the previous day's hike up the mountain? Is the probability closest to (A) 99% or (B) 50% or (C) 0.1% ?

Naming Names

In each equation below, part of a common name has been replaced with a definition for a word that is contained within that name. By answering the definition and completing the equation, you will find the name. (Ric + difficult = ric + hard = Richard)

Hint: Each is a girl's name.

1. Wrath + ne =
2. O + friend =
3. I + morose + ora =
4. B + building extension + e =
5. S + relate a story + a =

Born Liars

Edward, Howard, and John are three high school students each of whom is taking three of the four subjects, biology, chemistry, history, and mathematics. One day while talking about their programs they made the following statements.

Edward: There is just one subject we're all taking. I'm the only one of us who is taking mathematics. No two of us are taking the same three subjects. John is wrong when he says that Howard and I are both taking chemistry.

Howard: Ed is the only one of us who is taking history. John and I are taking the same subjects. We're all taking biology. Two of us are taking both chemistry and biology.

John: We're all taking mathematics. Howard is taking history. Ed is taking one subject that I'm not. Both Howard and Ed are taking chemistry.

If two and only two of each boy's statements are true, what subjects is each boy taking?

Take the Blue Pill

You've been placed on a course of expensive medication in which you are to take one tablet of Sildenafil and one tablet of Citrate daily. You must be careful that you take just one of each because taking more of either can have serious side effects.

Taking Sildenafil without taking Citrate, or vice versa, can also be very serious, because they must be taken together in order to be effective. In summary, you must take exactly one of the Sildenafil pills and one of the Citrate pills at one time. Therefore, you open up the Sildenafil bottle, and you tap one Sildenafil pill into your hand. You put that bottle aside and you open the Citrate bottle. You do the same, but by mistake, two Citrates fall into your hand with the Sildenafil pill.

Now, here's the problem. You weren't watching your hand as the pills fell into it, so you can't tell the Sildenafil pill apart from the two Citrate pills. The pills look identical. They are both the same size, same weight (10 micrograms), same color (Blue), same shape (perfect square), same everything, and they are not marked differently in any way.

What are you going to do? You cannot tell which pill is which, and they cost $300 a piece, so you cannot afford to throw them away and start over again. How do you get your daily dose of exactly one Sildenafil and exactly one Citrate without wasting any of the pills?