Figuring out how much air you
breathe during a lifetime is another fun
mathematical calculation. If you opti-
mistically decide you want to eventually
be 100 years old, and the average person
inhales about one pint (or 0.47 liters) of
air per breath, you can do the math. First
take the number of breaths you take
while at rest per minute (say about 21 per
minute) 0.47 liters 60 minutes 24
hours 365.25 days 100 years old
519,122,520 liters. Again, this is only an
approximation.What is the Monty Hall Problem?
Let’s Make a Deal,a once-popular televi-
sion game show with host Monty Hall
(who was the master of ceremonies from 1963 to 1986), is the origin of the Monty Hall
Problem. The same type of problem is also represented in a card game called “three-
card monte.”
The Monty Hall Problem is similar to the show. A contestant is given a choice of
three doors. Behind one is a car; behind the other two there is nothing. The host asks
the contestant to pick a door. After the pick, the host opens one of the unpicked
doors—one the host knows is empty. The host then suggests a switch. The big ques-
tion, and the problem, becomes does the contestant switch his or her choice or keep
the originally chosen door?
The mathematical, statistical answer is yes, switch the doors. Why? Because the
original probability that the contestant picked the correct door does not change—it is
still 1/3. But if the contestant does switch, the probability becomes 2/3. Most people
believe that once one of the doors is eliminated, the probability between the remain-
ing doors becomes 50-50, but it does not.How can people calculate their ageand weight on other planets?
It is certainly possible to find a person’s age and weight on another planet without
actually having to travel there. To figure out weight, one just needs to know the gravi-
tational pull on another planet, moon, or other space body. For example, based on the
chart below, if a person weighed 100 pounds on Earth, he or she would weigh 38
pounds on Mercury (100 0.38).
A person’s age on Earth depends on how many times the planet has orbited the
440 Sun during his or her lifetime. For example, a person 30 years old has traveled around
This astronaut on the Moon weighs only 17 percent
of what he would weigh if he were standing on the
Earth. Photographer’s Choice/Getty Images.