WASHINGTON STATE MATHEMATICS COUNCIL 1999 MIDDLE SCHOOL MATH OLYMPIAD EIGHTH GRADE PROBABILITY & STATISTICS Make sure you include proper units in your answer! 8

 1 The students in Ms. Hopkins' class collected data from the students in their school that resulted in the percentages at right. What is the fewest number of students who could have contributed data to the study? Favorite Pet Dog 24% Cat 20% Horse 18.75% Bird 16% Hamster 12.5% Fish 6.25% Lizard 2.5%

1. The eighth grade class at Mt. Kamiah elects four representatives to student council. There are 28 students in the eighth grade class. How many ways are there to choose four student council representatives, if all of the students are interested in the positions and if the order of the representatives does not make a difference?

3. An urn contains one gold coin and one silver coin. A second urn contains two gold coins and one silver coins. A coin is drawn at random from the first urn and dropped into the second urn. Then a coin is drawn from the second urn. What is the probability that the coin drawn from the second urn will be a gold coin? State your answer as a fraction.

4. Jennifer has 50 dollar bills stuffed in a jar in her room. There are half as many five dollar bills as there are one dollar bills. There are one-third as many tens as there are ones. There are half as many twenties as there are fives. If Jennifer reaches into the jar and randomly pulls out a bill, what is the probability that the bill will be a twenty? State your answer as a fraction.

5. If the squares of the first 30 positive numbers are used as a sample, based on this sample what four digits (0 through 9) have the highest probability of being found in the one's place of the squares of positive numbers?