2007 袋鼠数学 C-Benjamin 真题 答案 详解

英文真题

INTERNATIONAL KANGAROO MATHEMATICS CONTEST 2007 Level Benjamin: Class (5 & 6) Max Time: 1 Hour & 15 Minutes 3-Point-Problems Q1. Asia walks from the left to the right and puts the numbers in her basket. Which of the following numbers can be in her basket? A) 1, 2 and 4 B) 2, 3 and 4 C) 2, 3 and 5 D) 1, 5 and 6 Q2. Which piece fits together with the given one to form a rectangle? A) B) C) D) Q3. A kangaroo takes 6 seconds for every 4 jumps. How long does it take her to do 10 jumps? A) 15 B) 12 C) 10 D) 18 Q4. 2007÷(2+0+0+7)-2×0×0×7=? A) 9 B) 214 C) 223 D) 2007 Q5. Usman, who is older than Ali by 1 year minus 1 day, was born on January 1, 2002. What is the date of Ali's birth? A) January 2, 2003 B) January 2, 2001 C) December 31, 2000 D) December 31, 2002 1 of 4

真题文字详解(英文)

International Contest-Game MATH KANGAROO Canada, 2007 Grade 5 and 6 SOLUTIONS Part A: Each correct answer is worth 3 points. 1. Which of the five pieces below fits together with the one given on the right to form a rectangle? Solution: The piece completing the given figure has to contain an L-shape with two adjacent rows of 4 and 3 squares (to fit the part shown). Answer: B. 2. It takes Kanga the Kangaroo 6 seconds for every 4 jumps. How long does it take her to do 10 jumps? A) 10 sec. B) 12 sec. C) 15 sec. D) 18 sec. E) 20 sec. Solution: Since it takes 6 seconds for every 4 jumps, it will take 3 seconds for every 2 jumps. Therefore, it will take (10/2)x3=15 seconds to do 10 jumps. Answer: C. 3. Zita walked from the left to the right and wrote the numbers she saw along the roads in her notepad. Which of the following groups of numbers could be the numbers written by Zita? A) 1,2 and 4 B) 2,3 and 4 C) 2,3 and 5 D) 1,5 and 6 E) 1,2 and 5 Solution: Since Zita walked from left to right, she had to pass by only one of the numbers in each group of two elements ({1,2}; {3,4}; {5,6}). Answer: C ({1,2}; {3,4}; {5,6}). 4. What is the value of $2007 \div (2 + 0 + 0 + 7) - 2 \times 0 \times 0 \times 7$? A) 0 B) 9 C) 204 D) 223 E) 2007 Solution: It is important to follow the Order of Operations Rules. The expression simplifies to 2007/9=223. Answer: D