2015 澳洲 AMC C-Junior 真题 答案 详解

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中英双语真题

初级卷

1-10 题，每题3分

1. 算式2015 + 201.5等于
   (A) 2036.5 (B) 2116.5 (C) 2225.5 (D) 2216.5 (E) 2115.5

2. 在右图中，请问角x是什么？
   (A) 100° (B) 130° (C) 110° (D) 120° (E) 90°

3. 我必须在早上9:05 抵达学校，若从家中到学校费时23分钟，请问最晚我必须于什么时刻从家里出发？
   (A) 早上8:46 (B) 早上8:37 (C) 早上8:52 (D) 早上8:42 (E) 早上8:48

4. 请问100枚二十分钱的硬币共值多少元？
   (A) 20元 (B) 10元 (C) 200元 (D) 2元 (E) 100元

5. 请问如右图所示的直角三角形之面积为多少cm²？
   (A) 10 (B) 12 (C) 14 (D) 7 (E) 6

6. 当上课钟响起时，有3位教师与6位学生在教室里，有几名学生迟到了。当所有人都到齐后，老师人数与学生人数的比为1比4。请问有几位学生迟到？
   (A) 18 (B) 12 (C) 6 (D) 3 (E) 9

7. 有部电影片长2(\frac{1}{3})小时，这部电影被分为等长的二节。请问每节片长多少分钟？
   (A) 85 (B) 70 (C) 80 (D) 65 (E) 75

英文真题

Junior Division
Questions 1 to 10, 3 marks each

1. 2015 + 201.5 equals
   (A) 2036.5 (B) 2116.5 (C) 2225.5 (D) 2216.5 (E) 2115.5

2. The value of x in the diagram is
   (A) 100° (B) 130° (C) 110° (D) 120° (E) 90°

3. The trip to school takes 23 minutes. I need to be at school at 9:05 am. The latest I can leave home is
   (A) 8:46 am (B) 8:37 am (C) 8:52 am (D) 8:42 am (E) 8:48 am

4. What is the value of 100 twenty-cent coins?
   (A) $20 (B) $10 (C) $200 (D) $2 (E) $100

5. What is the area of this triangle in square centimetres?
   (A) 10 (B) 12 (C) 14 (D) 7 (E) 6

6. When the bell rang, there were 3 teachers and 6 students in the classroom. Several students arrived after the bell. Once everyone had arrived, there were 4 students for every teacher. How many students arrived after the bell?
   (A) 18 (B) 12 (C) 6 (D) 3 (E) 9

7. A movie lasts for (2\frac{1}{3}) hours. The movie is shown in two equal sessions. For how many minutes does each session last?
   (A) 85 (B) 70 (C) 80 (D) 65 (E) 75

真题文字详解(英文)

Solutions – Junior Division 1. 2015 + 201.5 = 2216.5, hence (D). 2. The three angles add to 180°, so x° = 110°, hence (C). 3. Since 23 minutes before 9:05 am is 18 minutes before 9 am, the latest I can leave home is 8:42 am, hence (D). 4. Alternative 1 100 times 1 c is $1, so 100 times 20 c is $20, hence (A). Alternative 2 There are 5 twenty-cent coins for every dollar, and 100 ÷ 5 = 20, hence (A). 5. (Also II) The area is (\frac{1}{2} \times 12 \times 2 = 12) cm², hence (B). 6. Since there were 3 teachers, there would be 12 students in all. Six of these were there on time, so 6 arrived after the bell, hence (C). 7. (Also I2) The movie lasts for 120 + 20 = 140 minutes, so each half is 140 ÷ 2 = 70 minutes, hence (B). 8. Counting unit lengths, (A) has perimeter 10, (B) has perimeter 10, and (D) has perimeter 8. The perimeter of (C) is (8 + 4 \times \frac{1}{2} = 10) and the perimeter of (E) is (10 + 2 \times \frac{1}{2} = 11), hence (E). 9. Bryce is 186 − 14 = 172 cm tall. Cy is 172 + 6 = 178 cm tall. Eric is 178 + 11 = 189 cm tall, hence (D). 2015 AMC – Junior Solutions http://anzexams.com