2022 袋鼠数学 C-Benjamin 真题 答案 详解

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中英双语真题

MATH KANGAROO CHINA Math Kangaroo 2022 (China) - Level 3 ASDAN China 3 points 1. Six points are numbered as shown. Kirsten draws two triangles, one by joining the even numbered points and one by joining the odd numbered points, and colours the inside of one of the triangles red and the inside of the other green. Which of the five options shows the picture Kirsten draws? 六个点的编号如右图所示。克里斯将编号都是偶数的点连接起来，将编号都是奇数的点连接起来，构成两个三角形，并将其中一个三角形涂成红色，另一个涂成绿色。请问下面哪个选项是克里斯画的图？ (A) (B) (C) (D) (E) 2. Eileen rowed around five buoys, as shown. Which buoys did Eileen row around in an anticlockwise direction? 艾琳绕着五个浮标划船，如图所示。请问她绕着哪几个浮标划船时是逆时针方向？ (A) 1 and 4 1和4 (B) 2, 3 and 5 2、3和5 (C) 2 and 3 2和3 (D) 1, 4 and 5 1、4和5 (E) 1 and 3 1和3 3. Laser beams reflect in mirrors in the way shown in the picture. At which letter will this laser beam end? 激光束在镜子中的反射情况如右图所示。那么下图中的激光束将从哪个字母的位置反射出来？ (A) A (B) B (C) C (D) D (E) E

真题文字详解(英文)

Benjamin Finalized
3 points

1 (MX). Six points are numbered as shown. Kirsten draws two triangles, one by joining the even numbered points and one by joining the odd numbered points, and colours the inside of one of the triangles red and the inside of the other green. Which of the five options shows the picture Kirsten draws?
(A)
(B)
(C)
(D)
(E)

Solution: 1, 3 and 5 are odd numbers; 2, 4 and 6 are even numbers. Connecting these three points you get the drawing E.

2 (DE). Eileen rowed around five buoys, as shown. Which buoys did Eileen row around in an anticlockwise direction?
(A) 1 and 4
(B) 2, 3 and 5
(C) 2 and 3
(D) 1, 4 and 5
(E) 1 and 3

Solution: When Eileen turns around a buoy in counterclockwise direction, the buoy is at her left. This is the case only with buoys 1 and 3, so the solution is E.

3 (DK). Laser beams reflect in mirrors in the way shown in the picture. At which letter will this laser beam end?
(A) A
(B) B
(C) C
(D) D
(E) E

Solution: It reaches the letter B.