John rolls a fair dice and Jack flips a fair coin. If Jack flips a head, then John's gets money equivalent to triple his dice roll. If Jack flips a tail, then John gets nothing. What is the expected value of John's winnings?
21/4
What is the least possible value of for real numbers and ?
1
In a plane, four circles with radii and are tangent to line at the same point but they may be on either side of . Region consists of all the points that lie inside exactly one of the four circles. What is the maximum possible area of region ?
65pi
The base-nine representation of the number is What is the remainder when is divided by
3
How many strings of length 7 containing only 0s, 1s, and 2s have no two consecutive 0s?
1244
Johann has 64 fair coins. He flips all the coins. Any coin that lands on tails is tossed again. Coins that land on tails on the second toss are tossed a third time. What is the expected number of coins that are now heads?
56
Consider the set of all fractions , where and are relatively prime positive integers. How many of these fractions have the property that if both numerator and denominator are increased by , the value of the fraction is increased by ?
1
All three vertices of are lying on the parabola defined by , with at the origin and parallel to the -axis. The area of the triangle is . What is the length of ?
8
How many of the first numbers in the sequence are divisible by ?
505
Suppose that one of every 500 people in a certain population has a particular disease, which displays no symptoms. A blood test is available for screening for this disease. For a person who has this disease, the test always turns out positive. For a person who does not have the disease, however, there is a false positive rate--in other words, for such people, of the time the test will turn out negative, but of the time the test will turn out positive and will incorrectly indicate that the person has the disease. Let be the probability that a person who is chosen at random from this population and gets a positive test result actually has the disease. Which of the following is closest to ?
1/11
Consider the paths of length that follow the lines from the lower left corner to the upper right corner on an grid. Find the number of such paths that change direction exactly four times, as in the examples shown below.
294
Let be the unique polynomial of minimal degree with the following properties:
The roots of are integers, with one exception. The root that is not an integer can be written as , where and are relatively prime integers. What is ?
47
In triangle , , , and . Distinct points , , and lie on segments , , and , respectively, such that , , and . The length of segment can be written as , where and are relatively prime positive integers. What is ?
21
How many distinct values of satisfy , where denotes the largest integer less than or equal to ?
4
Let , , and be positive integers with such that and .
What is ?
253