2012 袋鼠数学 D-Cadet 真题 答案 详解

英文真题

International Kangaroo Mathematics Contest 2012 - Cadet Level Cadet (Class 7 & 8) Time Allowed : 3 hours SECTION ONE - (3 points problems) 1. Four chocolate bars cost 6 EUR more than one chocolate bar. What is the cost of one chocolate bar? (A) 1 EUR (B) 2 EUR (C) 3 EUR (D) 4 EUR (E) 5 EUR 2. 11.11 - 1.111 = (A) 9.009 (B) 9.0909 (C) 9.99 (D) 9.999 (E) 10 3. A watch is placed face up on a table so that its minute hand points north-east. How many minutes pass before the minute hand points north-west for the first time? (A) 45 (B) 40 (C) 30 (D) 20 (E) 15 4. Mary has a pair of scissors and five cardboard letters. She cuts each letter exactly once (along a straight line) so that it falls apart in as many pieces as possible. Which letter falls apart into the most pieces? O F S H M (A) (B) (C) (D) (E) 5. A dragon has five heads. Every time a head is chopped off, five new heads grow. If six heads are chopped off one by one, how many heads will the dragon finally have? (A) 25 (B) 28 (C) 29 (D) 30 (E) 35 6. In which of the following expressions can we replace each occurrence of the number 8 by the same positive number (other than 8) and obtain the same result? (A) (8+8):8+8 (B) 8:(8+8):8 (C) 8+8-8+8 (D) (8+8-8).8 (E) (8+8-8):8 7. Each of the nine paths in a park is 100 m long. Ann wants to go from A to B without going along any path more than once. What is the length of the longest route she can choose?