Math Olympiad 5( Week 10 Quiz 2) 3. There are 18 triangles. Each triangle has exact one shared side with another triangle. How many sides are there in total? 4. A book has 300 pages numbered 1, 2, 3, ... and so on. In how many pages does the digit 9 appear more than once in the page number? 5. A quadrilateral is a polygon with four sides. A trapezoid is a quadrilateral with only one pair of parallel sides. A parallelogram is a quadrilateral with two pairs of parallel sides. A rectangle is a quadrilateral with four right angles. A rhombus is a quadrilateral with four sides of equal length. A square is a quadrilateral with all four sides of equal length and four right angles. 
Is a square always a parallelogram? 6. The following shape contains 17 identical squares. The area of the shape is 17 square feet. What is the perimeter (in feet) of the shape? 7. What is the value of |A − B| + |B − A| if A = -8 and B = -16? 8. If S = 4, T = 6 and U = 5, what is the value of S2 − (T − U)2? 9. If x = 1 and y = -1, what is the value of 4|x − 6y| − |7xy| ? 10. P and Q are natural numbers and P + Q = 19. What is the largest possible value of + ? 12. What is the product of (1 + )(1 + )(1 + )(1 + )(1 + )? 13. Deducting a number by and then adding the result by is equivalent to performing which of the following operations on the number? 14. What is the sum of all two-digit numbers that have at least one digit being 9? |