A Pop Quiz About Percentages and Probabilities
Some of these are purely math problems. Others have confounding issues beyond pure math. In other words, they are trick questions. Good luck.
1. If you were at a party with 30 people, assuming no-one was born on February 29th, what are the chances two of them share the same birthday?
2. Assume a hypothetical disease, call it Terry's Syndrome (TS). On average, one in 1,000 people get TS. The standard test for TS has a 0.9% false positive rate. The test also has a 0% false negative rate, if the test is negative you do not have it. If you test positive, what is the probability you actually have TS?
3. Say you were a baseball manager in the American League, so you had a designated hitter. Say you had nine really good hitters and you wanted to try every possible lineup combination to see what worked best. The baseball season is 162 games. If you began on opening day of the 2008 season, when would you run out of possibilities?
4. 850 people accidentally get a 15% lethal dose of some toxic substance. How many people would you expect to die from this?
5. You're at the craps table in Vegas and have rolled 5 straight sevens. What are the odds of rolling a 6th straight seven?
6. What percentage of the fruits and vegetables the average American consumes are organic?
7. You are given a choice of three secret prizes in boxes, knowing two are worthless and one is a winner. After making a choice one of the unchosen boxes is opened revealing a worthless prize. You are then given the option of switching your choice between the two unopened boxes. Should you do it?
8. If 87% of the leading scientists and 43% of the general population accept the new Colon Hypothesis of Gravitational Vorticity (CHGV), what are the chances that it's correct?
9. If you neutered 50% of male cats, what percentage reduction in cat reproductive capacity would you get?
10. If you can fool 60% of the people 100% of the time, and 100% of the people 70% of the time, how likely are you to be elected to Congress?