Question 1
Mary thought of a positive two-digit number. She multiplied it by and added . Then she switched the digits of the result, obtaining a number between and , inclusive. What was Mary's number?
Solution
Question 2
Sofia ran laps around the -meter track at her school. For each lap, she ran the first meters at an average speed of meters per second and the remaining meters at an average speed of meters per second. How much time did Sofia take running the laps?
Solution
Question 3
Real numbers , , and satisfy the inequalities , , and . Which of the following numbers is necessarily positive?
Solution
Question 4
Suppose that and are nonzero real numbers such that . What is the value of ?
Solution
Question 5
Camilla had twice as many blueberry jelly beans as cherry jelly beans. After eating pieces of each kind, she now has three times as many blueberry jelly beans as cherry jelly beans. How many blueberry jelly beans did she originally have?
Solution
Question 6
What is the largest number of solid by by blocks that can fit in a by by box?
Solution
Question 7
Samia set off on her bicycle to visit her friend, traveling at an average speed of kilometers per hour. When she had gone half the distance to her friend's house, a tire went flat, and she walked the rest of the way at kilometers per hour. In all it took her minutes to reach her friend's house. In kilometers rounded to the nearest tenth, how far did Samia walk?
Solution
Question 8
Points and are vertices of with . The altitude from meets the opposite side at . What are the coordinates of point ?
Solution
Question 9
A radio program has a quiz consisting of multiple-choice questions, each with choices. A contestant wins if he or she gets or more of the questions right. The contestant answers randomly to each question. What is the probability of winning?
Solution
Question 10
The lines with equations and are perpendicular and intersect at . What is ?
Solution
Question 11
At Typico High School, of the students like dancing, and the rest dislike it. Of those who like dancing, say that they like it, and the rest say that they dislike it. Of those who dislike dancing, say that they dislike it, and the rest say that they like it. What fraction of students who say they dislike dancing actually like it?
Solution
Question 12
Elmer's new car gives better fuel efficiency. However, the new car uses diesel fuel, which is more expensive per liter than the gasoline the old car used. By what percent will Elmer save money if he uses his new car instead of his old car for a long trip?
Solution
Question 13
There are students participating in an after-school program offering classes in yoga, bridge, and painting. Each student must take at least one of these three classes, but may take two or all three. There are students taking yoga, taking bridge, and taking painting. There are students taking at least two classes. How many students are taking all three classes?
Solution
Question 14
An integer is selected at random in the range . What is the probability that the remainder when is divided by is ?
Solution
Question 15
Rectangle has and . Point is the foot of the perpendicular from to diagonal . What is the area of ?
Solution
Question 16
How many of the base-ten numerals for the positive integers less than or equal to contain the digit ?
Solution
Question 17
Call a positive integer if it is a one-digit number or its digits, when read from left to right, form either a strictly increasing or a strictly decreasing sequence. For example, , , and are monotonous, but , , and are not. How many monotonous positive integers are there?
Solution
Question 18
In the figure below, of the disks are to be painted blue, are to be painted red, and is to be painted green. Two paintings that can be obtained from one another by a rotation or a reflection of the entire figure are considered the same. How many different paintings are possible?
Solution
Question 19
Let be an equilateral triangle. Extend side beyond to a point so that . Similarly, extend side beyond to a point so that , and extend side beyond to a point so that . What is the ratio of the area of to the area of ?
Solution
Question 20
The number has over positive integer divisors. One of them is chosen at random. What is the probability that it is odd?
Solution
Question 21
In , , , , and is the midpoint of . What is the sum of the radii of the circles inscribed in and ?
Solution
Question 22
The diameter of a circle of radius is extended to a point outside the circle so that . Point is chosen so that and line is perpendicular to line . Segment intersects the circle at a point between and . What is the area of ?
Solution
Question 23
Let be the -digit number that is formed by writing the integers from to in order, one after the other. What is the remainder when is divided by ?
Solution
Question 24
The vertices of an equilateral triangle lie on the hyperbola , and a vertex of this hyperbola is the centroid of the triangle. What is the square of the area of the triangle?
Solution
Question 25
Last year Isabella took math tests and received different scores, each an integer between and , inclusive. After each test she noticed that the average of her test scores was an integer. Her score on the seventh test was . What was her score on the sixth test?
Solution
Answer Keys
Question 1: B
Question 2: C
Question 3: E
Question 4: D
Question 5: D
Question 6: B
Question 7: C
Question 8: C
Question 9: D
Question 10: E
Question 11: D
Question 12: A
Question 13: C
Question 14: D
Question 15: E
Question 16: A
Question 17: B
Question 18: D
Question 19: E
Question 20: B
Question 21: D
Question 22: D
Question 23: C
Question 24: C
Question 25: E